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diff --git a/wqflask/utility/svg.py b/wqflask/utility/svg.py
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+# Copyright (C) University of Tennessee Health Science Center, Memphis, TN.
+#
+# This program is free software: you can redistribute it and/or modify it
+# under the terms of the GNU Affero General Public License
+# as published by the Free Software Foundation, either version 3 of the
+# License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+# See the GNU Affero General Public License for more details.
+#
+# This program is available from Source Forge: at GeneNetwork Project
+# (sourceforge.net/projects/genenetwork/).
+#
+# Contact Drs. Robert W. Williams and Xiaodong Zhou (2010)
+# at rwilliams@uthsc.edu and xzhou15@uthsc.edu
+#
+#
+#
+# This module is used by GeneNetwork project (www.genenetwork.org)
+#
+# Created by GeneNetwork Core Team 2010/08/10
+#
+# Last updated by GeneNetwork Core Team 2010/10/20
+
+#!/usr/bin/env python
+##Copyright (c) 2002, Fedor Baart & Hans de Wit (Stichting Farmaceutische Kengetallen)
+##All rights reserved.
+##
+##Redistribution and use in source and binary forms, with or without modification,
+##are permitted provided that the following conditions are met:
+##
+##Redistributions of source code must retain the above copyright notice, this
+##list of conditions and the following disclaimer.
+##
+##Redistributions in binary form must reproduce the above copyright notice,
+##this list of conditions and the following disclaimer in the documentation and/or
+##other materials provided with the distribution.
+##
+##Neither the name of the Stichting Farmaceutische Kengetallen nor the names of
+##its contributors may be used to endorse or promote products derived from this
+##software without specific prior written permission.
+##
+##THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+##AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+##IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+##DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
+##FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+##DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+##SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+##CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+##OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+##OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+##Thanks to Gerald Rosennfellner for his help and useful comments.
+
+__doc__="""Use SVGdraw to generate your SVGdrawings.
+
+SVGdraw uses an object model drawing and a method toXML to create SVG graphics
+by using easy to use classes and methods usualy you start by creating a drawing eg
+
+    d=drawing()
+    #then you create a SVG root element
+    s=svg()
+    #then you add some elements eg a circle and add it to the svg root element
+    c=circle()
+    #you can supply attributes by using named arguments.
+    c=circle(fill='red',stroke='blue')
+    #or by updating the attributes attribute:
+    c.attributes['stroke-width']=1
+    s.addElement(c)
+    #then you add the svg root element to the drawing
+    d.setSVG(s)
+    #and finaly you xmlify the drawing
+    d.toXml()
+
+
+this results in the svg source of the drawing, which consists of a circle
+on a white background. Its as easy as that;)
+This module was created using the SVG specification of www.w3c.org and the
+O'Reilly (www.oreilly.com) python books as information sources. A svg viewer
+is available from www.adobe.com"""
+
+__version__="1.0"
+
+# there are two possibilities to generate svg:
+# via a dom implementation and directly using <element>text</element> strings
+# the latter is way faster (and shorter in coding)
+# the former is only used in debugging svg programs
+# maybe it will be removed alltogether after a while
+# with the following variable you indicate whether to use the dom implementation
+# Note that PyXML is required for using the dom implementation.
+# It is also possible to use the standard minidom. But I didn't try that one.
+# Anyway the text based approach is about 60 times faster than using the full dom implementation.
+use_dom_implementation=0
+
+
+import exceptions
+if use_dom_implementation<>0:
+    try:
+        from xml.dom import implementation
+        from xml.dom.ext import PrettyPrint
+    except:
+        raise exceptions.ImportError, "PyXML is required for using the dom implementation"
+#The implementation is used for the creating the XML document.
+#The prettyprint module is used for converting the xml document object to a xml file
+
+import sys
+assert sys.version_info[0]>=2
+if sys.version_info[1]<2:
+    True=1
+    False=0
+    file=open
+
+sys.setrecursionlimit=50
+#The recursion limit is set conservative so mistakes like s=svg() s.addElement(s)
+#won't eat up too much processor time.
+
+#the following code is pasted form xml.sax.saxutils
+#it makes it possible to run the code without the xml sax package installed
+#To make it possible to have <rubbish> in your text elements, it is necessary to escape the texts
+def _escape(data, entities={}):
+    """Escape &, <, and > in a string of data.
+
+    You can escape other strings of data by passing a dictionary as
+    the optional entities parameter.  The keys and values must all be
+    strings; each key will be replaced with its corresponding value.
+    """
+    #data = data.replace("&", "&amp;")
+    data = data.replace("<", "&lt;")
+    data = data.replace(">", "&gt;")
+    for chars, entity in entities.items():
+        data = data.replace(chars, entity)
+    return data
+
+def _quoteattr(data, entities={}):
+    """Escape and quote an attribute value.
+
+    Escape &, <, and > in a string of data, then quote it for use as
+    an attribute value.  The \" character will be escaped as well, if
+    necessary.
+
+    You can escape other strings of data by passing a dictionary as
+    the optional entities parameter.  The keys and values must all be
+    strings; each key will be replaced with its corresponding value.
+    """
+    data = _escape(data, entities)
+    if '"' in data:
+        if "'" in data:
+            data = '"%s"' % data.replace('"', "&quot;")
+        else:
+            data = "'%s'" % data
+    else:
+        data = '"%s"' % data
+    return data
+
+
+
+def _xypointlist(a):
+    """formats a list of xy pairs"""
+    s=''
+    for e in a: #this could be done more elegant
+        s+=str(e)[1:-1] +'  '
+    return s
+
+def _viewboxlist(a):
+    """formats a tuple"""
+    s=''
+    for e in a:
+        s+=str(e)+' '
+    return s
+
+def _pointlist(a):
+    """formats a list of numbers"""
+    return str(a)[1:-1]
+
+class pathdata:
+    """class used to create a pathdata object which can be used for a path.
+    although most methods are pretty straightforward it might be useful to look at the SVG specification."""
+    #I didn't test the methods below.
+    def __init__(self,x=None,y=None):
+        self.path=[]
+        if x is not None and y is not None:
+            self.path.append('M '+str(x)+' '+str(y))
+    def closepath(self):
+        """ends the path"""
+        self.path.append('z')
+    def move(self,x,y):
+        """move to absolute"""
+        self.path.append('M '+str(x)+' '+str(y))
+    def relmove(self,x,y):
+        """move to relative"""
+        self.path.append('m '+str(x)+' '+str(y))
+    def line(self,x,y):
+        """line to absolute"""
+        self.path.append('L '+str(x)+' '+str(y))
+    def relline(self,x,y):
+        """line to relative"""
+        self.path.append('l '+str(x)+' '+str(y))
+    def hline(self,x):
+        """horizontal line to absolute"""
+        self.path.append('H'+str(x))
+    def relhline(self,x):
+        """horizontal line to relative"""
+        self.path.append('h'+str(x))
+    def vline(self,y):
+        """verical line to absolute"""
+        self.path.append('V'+str(y))
+    def relvline(self,y):
+        """vertical line to relative"""
+        self.path.append('v'+str(y))
+    def bezier(self,x1,y1,x2,y2,x,y):
+        """bezier with xy1 and xy2 to xy absolut"""
+        self.path.append('C'+str(x1)+','+str(y1)+' '+str(x2)+','+str(y2)+' '+str(x)+','+str(y))
+    def relbezier(self,x1,y1,x2,y2,x,y):
+        """bezier with xy1 and xy2 to xy relative"""
+        self.path.append('c'+str(x1)+','+str(y1)+' '+str(x2)+','+str(y2)+' '+str(x)+','+str(y))
+    def smbezier(self,x2,y2,x,y):
+        """smooth bezier with xy2 to xy absolut"""
+        self.path.append('S'+str(x2)+','+str(y2)+' '+str(x)+','+str(y))
+    def relsmbezier(self,x2,y2,x,y):
+        """smooth bezier with xy2 to xy relative"""
+        self.path.append('s'+str(x2)+','+str(y2)+' '+str(x)+','+str(y))
+    def qbezier(self,x1,y1,x,y):
+        """quadratic bezier with xy1 to xy absolut"""
+        self.path.append('Q'+str(x1)+','+str(y1)+' '+str(x)+','+str(y))
+    def relqbezier(self,x1,y1,x,y):
+        """quadratic bezier with xy1 to xy relative"""
+        self.path.append('q'+str(x1)+','+str(y1)+' '+str(x)+','+str(y))
+    def smqbezier(self,x,y):
+        """smooth quadratic bezier to xy absolut"""
+        self.path.append('T'+str(x)+','+str(y))
+    def relsmqbezier(self,x,y):
+        """smooth quadratic bezier to xy relative"""
+        self.path.append('t'+str(x)+','+str(y))
+    def ellarc(self,rx,ry,xrot,laf,sf,x,y):
+        """elliptival arc with rx and ry rotating with xrot using large-arc-flag and sweep-flag  to xy absolut"""
+        self.path.append('A'+str(rx)+','+str(ry)+' '+str(xrot)+' '+str(laf)+' '+str(sf)+' '+str(x)+' '+str(y))
+    def relellarc(self,rx,ry,xrot,laf,sf,x,y):
+        """elliptival arc with rx and ry rotating with xrot using large-arc-flag and sweep-flag  to xy relative"""
+        self.path.append('a'+str(rx)+','+str(ry)+' '+str(xrot)+' '+str(laf)+' '+str(sf)+' '+str(x)+' '+str(y))
+    def __repr__(self):
+        return ' '.join(self.path)
+
+
+
+
+class SVGelement:
+    """SVGelement(type,attributes,elements,text,namespace,**args)
+    Creates a arbitrary svg element and is intended to be subclassed not used on its own.
+    This element is the base of every svg element it defines a class which resembles
+    a xml-element. The main advantage of this kind of implementation is that you don't
+    have to create a toXML method for every different graph object. Every element
+    consists of a type, attribute, optional subelements, optional text and an optional
+    namespace. Note the elements==None, if elements = None:self.elements=[] construction.
+    This is done because if you default to elements=[] every object has a reference
+    to the same empty list."""
+    def __init__(self,type='',attributes=None,elements=None,text='',namespace='',cdata=None, **args):
+        self.type=type
+        if attributes==None:
+            self.attributes={}
+        else:
+            self.attributes=attributes
+        if elements==None:
+            self.elements=[]
+        else:
+            self.elements=elements
+        self.text=text
+        self.namespace=namespace
+        self.cdata=cdata
+        for arg in args.keys():
+            arg2 = arg.replace("__", ":")
+            arg2 = arg2.replace("_", "-")
+            self.attributes[arg2]=args[arg]
+    def addElement(self,SVGelement):
+        """adds an element to a SVGelement
+
+        SVGelement.addElement(SVGelement)
+        """
+        self.elements.append(SVGelement)
+
+    def toXml(self,level,f):
+        f.write('\t'*level)
+        f.write('<'+self.type)
+        for attkey in self.attributes.keys():
+            f.write(' '+_escape(str(attkey))+'='+_quoteattr(str(self.attributes[attkey])))
+        if self.namespace:
+            f.write(' xmlns="'+ _escape(str(self.namespace))+'" xmlns:xlink="http://www.w3.org/1999/xlink"')
+        if self.elements or self.text or self.cdata:
+            f.write('>')
+        if self.elements:
+            f.write('\n')
+        for element in self.elements:
+            element.toXml(level+1,f)
+        if self.cdata:
+            f.write('\n'+'\t'*(level+1)+'<![CDATA[')
+            for line in self.cdata.splitlines():
+                f.write('\n'+'\t'*(level+2)+line)
+            f.write('\n'+'\t'*(level+1)+']]>\n')
+        if self.text:
+            if type(self.text)==type(''): #If the text is only text
+                f.write(_escape(str(self.text)))
+            else:                         #If the text is a spannedtext class
+                f.write(str(self.text))
+        if self.elements:
+            f.write('\t'*level+'</'+self.type+'>\n')
+        elif self.text:
+            f.write('</'+self.type+'>\n')
+        elif self.cdata:
+            f.write('\t'*level+'</'+self.type+'>\n')
+        else:
+            f.write('/>\n')
+
+class tspan(SVGelement):
+    """ts=tspan(text='',**args)
+
+    a tspan element can be used for applying formatting to a textsection
+    usage:
+    ts=tspan('this text is bold')
+    ts.attributes['font-weight']='bold'
+    st=spannedtext()
+    st.addtspan(ts)
+    t=text(3,5,st)
+    """
+    def __init__(self,text=None,**args):
+        SVGelement.__init__(self,'tspan',**args)
+        if self.text<>None:
+            self.text=text
+    def __repr__(self):
+        s="<tspan"
+        for key,value in self.attributes.items():
+            s+= ' %s="%s"' % (key,value)
+        s+='>'
+        s+=self.text
+        s+='</tspan>'
+        return s
+
+class tref(SVGelement):
+    """tr=tref(link='',**args)
+
+    a tref element can be used for referencing text by a link to its id.
+    usage:
+    tr=tref('#linktotext')
+    st=spannedtext()
+    st.addtref(tr)
+    t=text(3,5,st)
+    """
+    def __init__(self,link,**args):
+        SVGelement.__init__(self,'tref',{'xlink:href':link},**args)
+    def __repr__(self):
+        s="<tref"
+
+        for key,value in self.attributes.items():
+            s+= ' %s="%s"' % (key,value)
+        s+='/>'
+        return s
+
+class spannedtext:
+    """st=spannedtext(textlist=[])
+
+    a spannedtext can be used for text which consists of text, tspan's and tref's
+    You can use it to add to a text element or path element. Don't add it directly
+    to a svg or a group element.
+    usage:
+
+    ts=tspan('this text is bold')
+    ts.attributes['font-weight']='bold'
+    tr=tref('#linktotext')
+    tr.attributes['fill']='red'
+    st=spannedtext()
+    st.addtspan(ts)
+    st.addtref(tr)
+    st.addtext('This text is not bold')
+    t=text(3,5,st)
+    """
+    def __init__(self,textlist=None):
+        if textlist==None:
+            self.textlist=[]
+        else:
+            self.textlist=textlist
+    def addtext(self,text=''):
+        self.textlist.append(text)
+    def addtspan(self,tspan):
+        self.textlist.append(tspan)
+    def addtref(self,tref):
+        self.textlist.append(tref)
+    def __repr__(self):
+        s=""
+        for element in self.textlist:
+            s+=str(element)
+        return s
+
+class rect(SVGelement):
+    """r=rect(width,height,x,y,fill,stroke,stroke_width,**args)
+
+    a rectangle is defined by a width and height and a xy pair
+    """
+    def __init__(self,x=None,y=None,width=None,height=None,fill=None,stroke=None,stroke_width=None,**args):
+        if width==None or height==None:
+            if width<>None:
+                raise ValueError, 'height is required'
+            if height<>None:
+                raise ValueError, 'width is required'
+            else:
+                raise ValueError, 'both height and width are required'
+        SVGelement.__init__(self,'rect',{'width':width,'height':height},**args)
+        if x<>None:
+            self.attributes['x']=x
+        if y<>None:
+            self.attributes['y']=y
+        if fill<>None:
+            self.attributes['fill']=fill
+        if stroke<>None:
+            self.attributes['stroke']=stroke
+        if stroke_width<>None:
+            self.attributes['stroke-width']=stroke_width
+
+class ellipse(SVGelement):
+    """e=ellipse(rx,ry,x,y,fill,stroke,stroke_width,**args)
+
+    an ellipse is defined as a center and a x and y radius.
+    """
+    def __init__(self,cx=None,cy=None,rx=None,ry=None,fill=None,stroke=None,stroke_width=None,**args):
+        if rx==None or ry== None:
+            if rx<>None:
+                raise ValueError, 'rx is required'
+            if ry<>None:
+                raise ValueError, 'ry is required'
+            else:
+                raise ValueError, 'both rx and ry are required'
+        SVGelement.__init__(self,'ellipse',{'rx':rx,'ry':ry},**args)
+        if cx<>None:
+            self.attributes['cx']=cx
+        if cy<>None:
+            self.attributes['cy']=cy
+        if fill<>None:
+            self.attributes['fill']=fill
+        if stroke<>None:
+            self.attributes['stroke']=stroke
+        if stroke_width<>None:
+            self.attributes['stroke-width']=stroke_width
+
+
+class circle(SVGelement):
+    """c=circle(x,y,radius,fill,stroke,stroke_width,**args)
+
+    The circle creates an element using a x, y and radius values eg
+    """
+    def __init__(self,cx=None,cy=None,r=None,fill=None,stroke=None,stroke_width=None,**args):
+        if r==None:
+            raise ValueError, 'r is required'
+        SVGelement.__init__(self,'circle',{'r':r},**args)
+        if cx<>None:
+            self.attributes['cx']=cx
+        if cy<>None:
+            self.attributes['cy']=cy
+        if fill<>None:
+            self.attributes['fill']=fill
+        if stroke<>None:
+            self.attributes['stroke']=stroke
+        if stroke_width<>None:
+            self.attributes['stroke-width']=stroke_width
+
+class point(circle):
+    """p=point(x,y,color)
+
+    A point is defined as a circle with a size 1 radius. It may be more efficient to use a
+    very small rectangle if you use many points because a circle is difficult to render.
+    """
+    def __init__(self,x,y,fill='black',**args):
+        circle.__init__(self,x,y,1,fill,**args)
+
+class line(SVGelement):
+    """l=line(x1,y1,x2,y2,stroke,stroke_width,**args)
+
+    A line is defined by a begin x,y pair and an end x,y pair
+    """
+    def __init__(self,x1=None,y1=None,x2=None,y2=None,stroke=None,stroke_width=None,**args):
+        SVGelement.__init__(self,'line',**args)
+        if x1<>None:
+            self.attributes['x1']=x1
+        if y1<>None:
+            self.attributes['y1']=y1
+        if x2<>None:
+            self.attributes['x2']=x2
+        if y2<>None:
+            self.attributes['y2']=y2
+        if stroke_width<>None:
+            self.attributes['stroke-width']=stroke_width
+        if stroke<>None:
+            self.attributes['stroke']=stroke
+
+class polyline(SVGelement):
+    """pl=polyline([[x1,y1],[x2,y2],...],fill,stroke,stroke_width,**args)
+
+    a polyline is defined by a list of xy pairs
+    """
+    def __init__(self,points,fill=None,stroke=None,stroke_width=None,**args):
+        SVGelement.__init__(self,'polyline',{'points':_xypointlist(points)},**args)
+        if fill<>None:
+            self.attributes['fill']=fill
+        if stroke_width<>None:
+            self.attributes['stroke-width']=stroke_width
+        if stroke<>None:
+            self.attributes['stroke']=stroke
+
+class polygon(SVGelement):
+    """pl=polyline([[x1,y1],[x2,y2],...],fill,stroke,stroke_width,**args)
+
+    a polygon is defined by a list of xy pairs
+    """
+    def __init__(self,points,fill=None,stroke=None,stroke_width=None,**args):
+        SVGelement.__init__(self,'polygon',{'points':_xypointlist(points)},**args)
+        if fill<>None:
+            self.attributes['fill']=fill
+        if stroke_width<>None:
+            self.attributes['stroke-width']=stroke_width
+        if stroke<>None:
+            self.attributes['stroke']=stroke
+
+class path(SVGelement):
+    """p=path(path,fill,stroke,stroke_width,**args)
+
+    a path is defined by a path object and optional width, stroke and fillcolor
+    """
+    def __init__(self,pathdata,fill=None,stroke=None,stroke_width=None,id=None,**args):
+        SVGelement.__init__(self,'path',{'d':str(pathdata)},**args)
+        if stroke<>None:
+            self.attributes['stroke']=stroke
+        if fill<>None:
+            self.attributes['fill']=fill
+        if stroke_width<>None:
+            self.attributes['stroke-width']=stroke_width
+        if id<>None:
+            self.attributes['id']=id
+
+
+class text(SVGelement):
+    """t=text(x,y,text,font_size,font_family,**args)
+
+    a text element can bge used for displaying text on the screen
+    """
+    def __init__(self,x=None,y=None,text=None,font_size=None,font_family=None,text_anchor=None,**args):
+        SVGelement.__init__(self,'text',**args)
+        if x<>None:
+            self.attributes['x']=x
+        if y<>None:
+            self.attributes['y']=y
+        if font_size<>None:
+            self.attributes['font-size']=font_size
+        if font_family<>None:
+            self.attributes['font-family']=font_family
+        if text<>None:
+            self.text=text
+        if text_anchor<>None:
+            self.attributes['text-anchor']=text_anchor
+
+
+class textpath(SVGelement):
+    """tp=textpath(text,link,**args)
+
+    a textpath places a text on a path which is referenced by a link.
+    """
+    def __init__(self,link,text=None,**args):
+        SVGelement.__init__(self,'textPath',{'xlink:href':link},**args)
+        if text<>None:
+            self.text=text
+
+class pattern(SVGelement):
+    """p=pattern(x,y,width,height,patternUnits,**args)
+
+    A pattern is used to fill or stroke an object using a pre-defined
+    graphic object which can be replicated ("tiled") at fixed intervals
+    in x and y to cover the areas to be painted.
+    """
+    def __init__(self,x=None,y=None,width=None,height=None,patternUnits=None,**args):
+        SVGelement.__init__(self,'pattern',**args)
+        if x<>None:
+            self.attributes['x']=x
+        if y<>None:
+            self.attributes['y']=y
+        if width<>None:
+            self.attributes['width']=width
+        if height<>None:
+            self.attributes['height']=height
+        if patternUnits<>None:
+            self.attributes['patternUnits']=patternUnits
+
+class title(SVGelement):
+    """t=title(text,**args)
+
+    a title is a text element. The text is displayed in the title bar
+    add at least one to the root svg element
+    """
+    def __init__(self,text=None,**args):
+        SVGelement.__init__(self,'title',**args)
+        if text<>None:
+            self.text=text
+
+class description(SVGelement):
+    """d=description(text,**args)
+
+    a description can be added to any element and is used for a tooltip
+    Add this element before adding other elements.
+    """
+    def __init__(self,text=None,**args):
+        SVGelement.__init__(self,'desc',**args)
+        if text<>None:
+            self.text=text
+
+class lineargradient(SVGelement):
+    """lg=lineargradient(x1,y1,x2,y2,id,**args)
+
+    defines a lineargradient using two xy pairs.
+    stop elements van be added to define the gradient colors.
+    """
+    def __init__(self,x1=None,y1=None,x2=None,y2=None,id=None,**args):
+        SVGelement.__init__(self,'linearGradient',**args)
+        if x1<>None:
+            self.attributes['x1']=x1
+        if y1<>None:
+            self.attributes['y1']=y1
+        if x2<>None:
+            self.attributes['x2']=x2
+        if y2<>None:
+            self.attributes['y2']=y2
+        if id<>None:
+            self.attributes['id']=id
+
+class radialgradient(SVGelement):
+    """rg=radialgradient(cx,cy,r,fx,fy,id,**args)
+
+    defines a radial gradient using a outer circle which are defined by a cx,cy and r and by using a focalpoint.
+    stop elements van be added to define the gradient colors.
+    """
+    def __init__(self,cx=None,cy=None,r=None,fx=None,fy=None,id=None,**args):
+        SVGelement.__init__(self,'radialGradient',**args)
+        if cx<>None:
+            self.attributes['cx']=cx
+        if cy<>None:
+            self.attributes['cy']=cy
+        if r<>None:
+            self.attributes['r']=r
+        if fx<>None:
+            self.attributes['fx']=fx
+        if fy<>None:
+            self.attributes['fy']=fy
+        if id<>None:
+            self.attributes['id']=id
+
+class stop(SVGelement):
+    """st=stop(offset,stop_color,**args)
+
+    Puts a stop color at the specified radius
+    """
+    def __init__(self,offset,stop_color=None,**args):
+        SVGelement.__init__(self,'stop',{'offset':offset},**args)
+        if stop_color<>None:
+            self.attributes['stop-color']=stop_color
+
+class style(SVGelement):
+    """st=style(type,cdata=None,**args)
+
+    Add a CDATA element to this element for defing in line stylesheets etc..
+    """
+    def __init__(self,type,cdata=None,**args):
+        SVGelement.__init__(self,'style',{'type':type},cdata=cdata, **args)
+
+
+class image(SVGelement):
+    """im=image(url,width,height,x,y,**args)
+
+    adds an image to the drawing. Supported formats are .png, .jpg and .svg.
+    """
+    def __init__(self,url,x=None,y=None,width=None,height=None,**args):
+        if width==None or height==None:
+            if width<>None:
+                raise ValueError, 'height is required'
+            if height<>None:
+                raise ValueError, 'width is required'
+            else:
+                raise ValueError, 'both height and width are required'
+        SVGelement.__init__(self,'image',{'xlink:href':url,'width':width,'height':height},**args)
+        if x<>None:
+            self.attributes['x']=x
+        if y<>None:
+            self.attributes['y']=y
+
+class cursor(SVGelement):
+    """c=cursor(url,**args)
+
+    defines a custom cursor for a element or a drawing
+    """
+    def __init__(self,url,**args):
+        SVGelement.__init__(self,'cursor',{'xlink:href':url},**args)
+
+
+class marker(SVGelement):
+    """m=marker(id,viewbox,refX,refY,markerWidth,markerHeight,**args)
+
+    defines a marker which can be used as an endpoint for a line or other pathtypes
+    add an element to it which should be used as a marker.
+    """
+    def __init__(self,id=None,viewBox=None,refx=None,refy=None,markerWidth=None,markerHeight=None,**args):
+        SVGelement.__init__(self,'marker',**args)
+        if id<>None:
+            self.attributes['id']=id
+        if viewBox<>None:
+            self.attributes['viewBox']=_viewboxlist(viewBox)
+        if refx<>None:
+            self.attributes['refX']=refx
+        if refy<>None:
+            self.attributes['refY']=refy
+        if markerWidth<>None:
+            self.attributes['markerWidth']=markerWidth
+        if markerHeight<>None:
+            self.attributes['markerHeight']=markerHeight
+
+class group(SVGelement):
+    """g=group(id,**args)
+
+    a group is defined by an id and is used to contain elements
+    g.addElement(SVGelement)
+    """
+    def __init__(self,id=None,**args):
+        SVGelement.__init__(self,'g',**args)
+        if id<>None:
+            self.attributes['id']=id
+
+class symbol(SVGelement):
+    """sy=symbol(id,viewbox,**args)
+
+    defines a symbol which can be used on different places in your graph using
+    the use element. A symbol is not rendered but you can use 'use' elements to
+    display it by referencing its id.
+    sy.addElement(SVGelement)
+    """
+
+    def __init__(self,id=None,viewBox=None,**args):
+        SVGelement.__init__(self,'symbol',**args)
+        if id<>None:
+            self.attributes['id']=id
+        if viewBox<>None:
+            self.attributes['viewBox']=_viewboxlist(viewBox)
+
+class defs(SVGelement):
+    """d=defs(**args)
+
+    container for defining elements
+    """
+    def __init__(self,**args):
+        SVGelement.__init__(self,'defs',**args)
+
+class switch(SVGelement):
+    """sw=switch(**args)
+
+    Elements added to a switch element which are "switched" by the attributes
+    requiredFeatures, requiredExtensions and systemLanguage.
+    Refer to the SVG specification for details.
+    """
+    def __init__(self,**args):
+        SVGelement.__init__(self,'switch',**args)
+
+
+class use(SVGelement):
+    """u=use(link,x,y,width,height,**args)
+
+    references a symbol by linking to its id and its position, height and width
+    """
+    def __init__(self,link,x=None,y=None,width=None,height=None,**args):
+        SVGelement.__init__(self,'use',{'xlink:href':link},**args)
+        if x<>None:
+            self.attributes['x']=x
+        if y<>None:
+            self.attributes['y']=y
+
+        if width<>None:
+            self.attributes['width']=width
+        if height<>None:
+            self.attributes['height']=height
+
+
+class link(SVGelement):
+    """a=link(url,**args)
+
+    a link  is defined by a hyperlink. add elements which have to be linked
+    a.addElement(SVGelement)
+    """
+    def __init__(self,link='',**args):
+        SVGelement.__init__(self,'a',{'xlink:href':link},**args)
+
+class view(SVGelement):
+    """v=view(id,**args)
+
+    a view can be used to create a view with different attributes"""
+    def __init__(self,id=None,**args):
+        SVGelement.__init__(self,'view',**args)
+        if id<>None:
+            self.attributes['id']=id
+
+class script(SVGelement):
+    """sc=script(type,type,cdata,**args)
+
+    adds a script element which contains CDATA to the SVG drawing
+
+    """
+    def __init__(self,type,cdata=None,**args):
+        SVGelement.__init__(self,'script',{'type':type},cdata=cdata,**args)
+
+class animate(SVGelement):
+    """an=animate(attribute,from,to,during,**args)
+
+    animates an attribute.
+    """
+    def __init__(self,attribute,fr=None,to=None,dur=None,**args):
+        SVGelement.__init__(self,'animate',{'attributeName':attribute},**args)
+        if fr<>None:
+            self.attributes['from']=fr
+        if to<>None:
+            self.attributes['to']=to
+        if dur<>None:
+            self.attributes['dur']=dur
+
+class animateMotion(SVGelement):
+    """an=animateMotion(pathdata,dur,**args)
+
+    animates a SVGelement over the given path in dur seconds
+    """
+    def __init__(self,pathdata,dur,**args):
+        SVGelement.__init__(self,'animateMotion',**args)
+        if pathdata<>None:
+            self.attributes['path']=str(pathdata)
+        if dur<>None:
+            self.attributes['dur']=dur
+
+class animateTransform(SVGelement):
+    """antr=animateTransform(type,from,to,dur,**args)
+
+    transform an element from and to a value.
+    """
+    def __init__(self,type=None,fr=None,to=None,dur=None,**args):
+        SVGelement.__init__(self,'animateTransform',{'attributeName':'transform'},**args)
+        #As far as I know the attributeName is always transform
+        if type<>None:
+            self.attributes['type']=type
+        if fr<>None:
+            self.attributes['from']=fr
+        if to<>None:
+            self.attributes['to']=to
+        if dur<>None:
+            self.attributes['dur']=dur
+class animateColor(SVGelement):
+    """ac=animateColor(attribute,type,from,to,dur,**args)
+
+    Animates the color of a element
+    """
+    def __init__(self,attribute,type=None,fr=None,to=None,dur=None,**args):
+        SVGelement.__init__(self,'animateColor',{'attributeName':attribute},**args)
+        if type<>None:
+            self.attributes['type']=type
+        if fr<>None:
+            self.attributes['from']=fr
+        if to<>None:
+            self.attributes['to']=to
+        if dur<>None:
+            self.attributes['dur']=dur
+class set(SVGelement):
+    """st=set(attribute,to,during,**args)
+
+    sets an attribute to a value for a
+    """
+    def __init__(self,attribute,to=None,dur=None,**args):
+        SVGelement.__init__(self,'set',{'attributeName':attribute},**args)
+        if to<>None:
+            self.attributes['to']=to
+        if dur<>None:
+            self.attributes['dur']=dur
+
+
+
+class svg(SVGelement):
+    """s=svg(viewbox,width,height,**args)
+
+    a svg or element is the root of a drawing add all elements to a svg element.
+    You can have different svg elements in one svg file
+    s.addElement(SVGelement)
+
+    eg
+    d=drawing()
+    s=svg((0,0,100,100),'100%','100%')
+    c=circle(50,50,20)
+    s.addElement(c)
+    d.setSVG(s)
+    d.toXml()
+    """
+    def __init__(self,viewBox=None, width=None, height=None,**args):
+        SVGelement.__init__(self,'svg',**args)
+        if viewBox<>None:
+            self.attributes['viewBox']=_viewboxlist(viewBox)
+        if width<>None:
+            self.attributes['width']=width
+        if height<>None:
+            self.attributes['height']=height
+        self.namespace="http://www.w3.org/2000/svg"
+
+class drawing:
+    """d=drawing()
+
+    this is the actual SVG document. It needs a svg element as a root.
+    Use the addSVG method to set the svg to the root. Use the toXml method to write the SVG
+    source to the screen or to a file
+    d=drawing()
+    d.addSVG(svg)
+    d.toXml(optionalfilename)
+    """
+
+    def __init__(self, entity={}):
+        self.svg=None
+        self.entity = entity
+    def setSVG(self,svg):
+        self.svg=svg
+        #Voeg een element toe aan de grafiek toe.
+    if use_dom_implementation==0:
+        def toXml(self, filename='',compress=False):
+            import cStringIO
+            xml=cStringIO.StringIO()
+            xml.write("<?xml version='1.0' encoding='UTF-8'?>\n")
+            xml.write("<!DOCTYPE svg PUBLIC \"-//W3C//DTD SVG 1.0//EN\" \"http://www.w3.org/TR/2001/REC-SVG-20010904/DTD/svg10.dtd\"")
+            if self.entity:
+                xml.write(" [\n")
+                for item in self.entity.keys():
+                    xml.write("<!ENTITY %s \"%s\">\n" % (item, self.entity[item]))
+                xml.write("]")
+            xml.write(">\n")
+            self.svg.toXml(0,xml)
+            if not filename:
+                if compress:
+                    import gzip
+                    f=cStringIO.StringIO()
+                    zf=gzip.GzipFile(fileobj=f,mode='wb')
+                    zf.write(xml.getvalue())
+                    zf.close()
+                    f.seek(0)
+                    return f.read()
+                else:
+                    return xml.getvalue()
+            else:
+                if filename[-4:]=='svgz':
+                    import gzip
+                    f=gzip.GzipFile(filename=filename,mode="wb", compresslevel=9)
+                    f.write(xml.getvalue())
+                    f.close()
+                else:
+                    f=file(filename,'w')
+                    f.write(xml.getvalue())
+                    f.close()
+
+    else:
+        def toXml(self,filename='',compress=False):
+            """drawing.toXml()        ---->to the screen
+            drawing.toXml(filename)---->to the file
+            writes a svg drawing to the screen or to a file
+            compresses if filename ends with svgz or if compress is true
+            """
+            doctype = implementation.createDocumentType('svg',"-//W3C//DTD SVG 1.0//EN""",'http://www.w3.org/TR/2001/REC-SVG-20010904/DTD/svg10.dtd ')
+
+            global root
+            #root is defined global so it can be used by the appender. Its also possible to use it as an arugument but
+            #that is a bit messy.
+            root=implementation.createDocument(None,None,doctype)
+            #Create the xml document.
+            global appender
+            def appender(element,elementroot):
+                """This recursive function appends elements to an element and sets the attributes
+                and type. It stops when alle elements have been appended"""
+                if element.namespace:
+                    e=root.createElementNS(element.namespace,element.type)
+                else:
+                    e=root.createElement(element.type)
+                if element.text:
+                    textnode=root.createTextNode(element.text)
+                    e.appendChild(textnode)
+                for attribute in element.attributes.keys():   #in element.attributes is supported from python 2.2
+                    e.setAttribute(attribute,str(element.attributes[attribute]))
+                if element.elements:
+                    for el in element.elements:
+                        e=appender(el,e)
+                elementroot.appendChild(e)
+                return elementroot
+            root=appender(self.svg,root)
+            if not filename:
+                import cStringIO
+                xml=cStringIO.StringIO()
+                PrettyPrint(root,xml)
+                if compress:
+                    import gzip
+                    f=cStringIO.StringIO()
+                    zf=gzip.GzipFile(fileobj=f,mode='wb')
+                    zf.write(xml.getvalue())
+                    zf.close()
+                    f.seek(0)
+                    return f.read()
+                else:
+                    return xml.getvalue()
+            else:
+                try:
+                    if filename[-4:]=='svgz':
+                        import gzip
+                        import cStringIO
+                        xml=cStringIO.StringIO()
+                        PrettyPrint(root,xml)
+                        f=gzip.GzipFile(filename=filename,mode='wb',compresslevel=9)
+                        f.write(xml.getvalue())
+                        f.close()
+                    else:
+                        f=open(filename,'w')
+                        PrettyPrint(root,f)
+                        f.close()
+                except:
+                    print "Cannot write SVG file: " + filename
+    def validate(self):
+        try:
+            import xml.parsers.xmlproc.xmlval
+        except:
+            raise exceptions.ImportError,'PyXml is required for validating SVG'
+        svg=self.toXml()
+        xv=xml.parsers.xmlproc.xmlval.XMLValidator()
+        try:
+            xv.feed(svg)
+        except:
+            raise Exception("SVG is not well formed, see messages above")
+        else:
+            print "SVG well formed"
+if __name__=='__main__':
+
+
+    d=drawing()
+    s=svg((0,0,100,100))
+    r=rect(-100,-100,300,300,'cyan')
+    s.addElement(r)
+
+    t=title('SVGdraw Demo')
+    s.addElement(t)
+    g=group('animations')
+    e=ellipse(0,0,5,2)
+    g.addElement(e)
+    c=circle(0,0,1,'red')
+    g.addElement(c)
+    pd=pathdata(0,-10)
+    for i in range(6):
+        pd.relsmbezier(10,5,0,10)
+        pd.relsmbezier(-10,5,0,10)
+    an=animateMotion(pd,10)
+    an.attributes['rotate']='auto-reverse'
+    an.attributes['repeatCount']="indefinite"
+    g.addElement(an)
+    s.addElement(g)
+    for i in range(20,120,20):
+        u=use('#animations',i,0)
+        s.addElement(u)
+    for i in range(0,120,20):
+        for j in range(5,105,10):
+            c=circle(i,j,1,'red','black',.5)
+            s.addElement(c)
+    d.setSVG(s)
+
+    print d.toXml()