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diff --git a/.venv/lib/python3.12/site-packages/pip/_vendor/resolvelib/structs.py b/.venv/lib/python3.12/site-packages/pip/_vendor/resolvelib/structs.py
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+++ b/.venv/lib/python3.12/site-packages/pip/_vendor/resolvelib/structs.py
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+import itertools
+
+from .compat import collections_abc
+
+
+class DirectedGraph(object):
+ """A graph structure with directed edges."""
+
+ def __init__(self):
+ self._vertices = set()
+ self._forwards = {} # <key> -> Set[<key>]
+ self._backwards = {} # <key> -> Set[<key>]
+
+ def __iter__(self):
+ return iter(self._vertices)
+
+ def __len__(self):
+ return len(self._vertices)
+
+ def __contains__(self, key):
+ return key in self._vertices
+
+ def copy(self):
+ """Return a shallow copy of this graph."""
+ other = DirectedGraph()
+ other._vertices = set(self._vertices)
+ other._forwards = {k: set(v) for k, v in self._forwards.items()}
+ other._backwards = {k: set(v) for k, v in self._backwards.items()}
+ return other
+
+ def add(self, key):
+ """Add a new vertex to the graph."""
+ if key in self._vertices:
+ raise ValueError("vertex exists")
+ self._vertices.add(key)
+ self._forwards[key] = set()
+ self._backwards[key] = set()
+
+ def remove(self, key):
+ """Remove a vertex from the graph, disconnecting all edges from/to it."""
+ self._vertices.remove(key)
+ for f in self._forwards.pop(key):
+ self._backwards[f].remove(key)
+ for t in self._backwards.pop(key):
+ self._forwards[t].remove(key)
+
+ def connected(self, f, t):
+ return f in self._backwards[t] and t in self._forwards[f]
+
+ def connect(self, f, t):
+ """Connect two existing vertices.
+
+ Nothing happens if the vertices are already connected.
+ """
+ if t not in self._vertices:
+ raise KeyError(t)
+ self._forwards[f].add(t)
+ self._backwards[t].add(f)
+
+ def iter_edges(self):
+ for f, children in self._forwards.items():
+ for t in children:
+ yield f, t
+
+ def iter_children(self, key):
+ return iter(self._forwards[key])
+
+ def iter_parents(self, key):
+ return iter(self._backwards[key])
+
+
+class IteratorMapping(collections_abc.Mapping):
+ def __init__(self, mapping, accessor, appends=None):
+ self._mapping = mapping
+ self._accessor = accessor
+ self._appends = appends or {}
+
+ def __repr__(self):
+ return "IteratorMapping({!r}, {!r}, {!r})".format(
+ self._mapping,
+ self._accessor,
+ self._appends,
+ )
+
+ def __bool__(self):
+ return bool(self._mapping or self._appends)
+
+ __nonzero__ = __bool__ # XXX: Python 2.
+
+ def __contains__(self, key):
+ return key in self._mapping or key in self._appends
+
+ def __getitem__(self, k):
+ try:
+ v = self._mapping[k]
+ except KeyError:
+ return iter(self._appends[k])
+ return itertools.chain(self._accessor(v), self._appends.get(k, ()))
+
+ def __iter__(self):
+ more = (k for k in self._appends if k not in self._mapping)
+ return itertools.chain(self._mapping, more)
+
+ def __len__(self):
+ more = sum(1 for k in self._appends if k not in self._mapping)
+ return len(self._mapping) + more
+
+
+class _FactoryIterableView(object):
+ """Wrap an iterator factory returned by `find_matches()`.
+
+ Calling `iter()` on this class would invoke the underlying iterator
+ factory, making it a "collection with ordering" that can be iterated
+ through multiple times, but lacks random access methods presented in
+ built-in Python sequence types.
+ """
+
+ def __init__(self, factory):
+ self._factory = factory
+ self._iterable = None
+
+ def __repr__(self):
+ return "{}({})".format(type(self).__name__, list(self))
+
+ def __bool__(self):
+ try:
+ next(iter(self))
+ except StopIteration:
+ return False
+ return True
+
+ __nonzero__ = __bool__ # XXX: Python 2.
+
+ def __iter__(self):
+ iterable = (
+ self._factory() if self._iterable is None else self._iterable
+ )
+ self._iterable, current = itertools.tee(iterable)
+ return current
+
+
+class _SequenceIterableView(object):
+ """Wrap an iterable returned by find_matches().
+
+ This is essentially just a proxy to the underlying sequence that provides
+ the same interface as `_FactoryIterableView`.
+ """
+
+ def __init__(self, sequence):
+ self._sequence = sequence
+
+ def __repr__(self):
+ return "{}({})".format(type(self).__name__, self._sequence)
+
+ def __bool__(self):
+ return bool(self._sequence)
+
+ __nonzero__ = __bool__ # XXX: Python 2.
+
+ def __iter__(self):
+ return iter(self._sequence)
+
+
+def build_iter_view(matches):
+ """Build an iterable view from the value returned by `find_matches()`."""
+ if callable(matches):
+ return _FactoryIterableView(matches)
+ if not isinstance(matches, collections_abc.Sequence):
+ matches = list(matches)
+ return _SequenceIterableView(matches)