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diff --git a/.venv/lib/python3.12/site-packages/sqlalchemy/orm/unitofwork.py b/.venv/lib/python3.12/site-packages/sqlalchemy/orm/unitofwork.py
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+# orm/unitofwork.py
+# Copyright (C) 2005-2025 the SQLAlchemy authors and contributors
+# <see AUTHORS file>
+#
+# This module is part of SQLAlchemy and is released under
+# the MIT License: https://www.opensource.org/licenses/mit-license.php
+# mypy: ignore-errors
+
+
+"""The internals for the unit of work system.
+
+The session's flush() process passes objects to a contextual object
+here, which assembles flush tasks based on mappers and their properties,
+organizes them in order of dependency, and executes.
+
+"""
+
+from __future__ import annotations
+
+from typing import Any
+from typing import Dict
+from typing import Optional
+from typing import Set
+from typing import TYPE_CHECKING
+
+from . import attributes
+from . import exc as orm_exc
+from . import util as orm_util
+from .. import event
+from .. import util
+from ..util import topological
+
+
+if TYPE_CHECKING:
+    from .dependency import DependencyProcessor
+    from .interfaces import MapperProperty
+    from .mapper import Mapper
+    from .session import Session
+    from .session import SessionTransaction
+    from .state import InstanceState
+
+
+def track_cascade_events(descriptor, prop):
+    """Establish event listeners on object attributes which handle
+    cascade-on-set/append.
+
+    """
+    key = prop.key
+
+    def append(state, item, initiator, **kw):
+        # process "save_update" cascade rules for when
+        # an instance is appended to the list of another instance
+
+        if item is None:
+            return
+
+        sess = state.session
+        if sess:
+            if sess._warn_on_events:
+                sess._flush_warning("collection append")
+
+            prop = state.manager.mapper._props[key]
+            item_state = attributes.instance_state(item)
+
+            if (
+                prop._cascade.save_update
+                and (key == initiator.key)
+                and not sess._contains_state(item_state)
+            ):
+                sess._save_or_update_state(item_state)
+        return item
+
+    def remove(state, item, initiator, **kw):
+        if item is None:
+            return
+
+        sess = state.session
+
+        prop = state.manager.mapper._props[key]
+
+        if sess and sess._warn_on_events:
+            sess._flush_warning(
+                "collection remove"
+                if prop.uselist
+                else "related attribute delete"
+            )
+
+        if (
+            item is not None
+            and item is not attributes.NEVER_SET
+            and item is not attributes.PASSIVE_NO_RESULT
+            and prop._cascade.delete_orphan
+        ):
+            # expunge pending orphans
+            item_state = attributes.instance_state(item)
+
+            if prop.mapper._is_orphan(item_state):
+                if sess and item_state in sess._new:
+                    sess.expunge(item)
+                else:
+                    # the related item may or may not itself be in a
+                    # Session, however the parent for which we are catching
+                    # the event is not in a session, so memoize this on the
+                    # item
+                    item_state._orphaned_outside_of_session = True
+
+    def set_(state, newvalue, oldvalue, initiator, **kw):
+        # process "save_update" cascade rules for when an instance
+        # is attached to another instance
+        if oldvalue is newvalue:
+            return newvalue
+
+        sess = state.session
+        if sess:
+            if sess._warn_on_events:
+                sess._flush_warning("related attribute set")
+
+            prop = state.manager.mapper._props[key]
+            if newvalue is not None:
+                newvalue_state = attributes.instance_state(newvalue)
+                if (
+                    prop._cascade.save_update
+                    and (key == initiator.key)
+                    and not sess._contains_state(newvalue_state)
+                ):
+                    sess._save_or_update_state(newvalue_state)
+
+            if (
+                oldvalue is not None
+                and oldvalue is not attributes.NEVER_SET
+                and oldvalue is not attributes.PASSIVE_NO_RESULT
+                and prop._cascade.delete_orphan
+            ):
+                # possible to reach here with attributes.NEVER_SET ?
+                oldvalue_state = attributes.instance_state(oldvalue)
+
+                if oldvalue_state in sess._new and prop.mapper._is_orphan(
+                    oldvalue_state
+                ):
+                    sess.expunge(oldvalue)
+        return newvalue
+
+    event.listen(
+        descriptor, "append_wo_mutation", append, raw=True, include_key=True
+    )
+    event.listen(
+        descriptor, "append", append, raw=True, retval=True, include_key=True
+    )
+    event.listen(
+        descriptor, "remove", remove, raw=True, retval=True, include_key=True
+    )
+    event.listen(
+        descriptor, "set", set_, raw=True, retval=True, include_key=True
+    )
+
+
+class UOWTransaction:
+    session: Session
+    transaction: SessionTransaction
+    attributes: Dict[str, Any]
+    deps: util.defaultdict[Mapper[Any], Set[DependencyProcessor]]
+    mappers: util.defaultdict[Mapper[Any], Set[InstanceState[Any]]]
+
+    def __init__(self, session: Session):
+        self.session = session
+
+        # dictionary used by external actors to
+        # store arbitrary state information.
+        self.attributes = {}
+
+        # dictionary of mappers to sets of
+        # DependencyProcessors, which are also
+        # set to be part of the sorted flush actions,
+        # which have that mapper as a parent.
+        self.deps = util.defaultdict(set)
+
+        # dictionary of mappers to sets of InstanceState
+        # items pending for flush which have that mapper
+        # as a parent.
+        self.mappers = util.defaultdict(set)
+
+        # a dictionary of Preprocess objects, which gather
+        # additional states impacted by the flush
+        # and determine if a flush action is needed
+        self.presort_actions = {}
+
+        # dictionary of PostSortRec objects, each
+        # one issues work during the flush within
+        # a certain ordering.
+        self.postsort_actions = {}
+
+        # a set of 2-tuples, each containing two
+        # PostSortRec objects where the second
+        # is dependent on the first being executed
+        # first
+        self.dependencies = set()
+
+        # dictionary of InstanceState-> (isdelete, listonly)
+        # tuples, indicating if this state is to be deleted
+        # or insert/updated, or just refreshed
+        self.states = {}
+
+        # tracks InstanceStates which will be receiving
+        # a "post update" call.  Keys are mappers,
+        # values are a set of states and a set of the
+        # columns which should be included in the update.
+        self.post_update_states = util.defaultdict(lambda: (set(), set()))
+
+    @property
+    def has_work(self):
+        return bool(self.states)
+
+    def was_already_deleted(self, state):
+        """Return ``True`` if the given state is expired and was deleted
+        previously.
+        """
+        if state.expired:
+            try:
+                state._load_expired(state, attributes.PASSIVE_OFF)
+            except orm_exc.ObjectDeletedError:
+                self.session._remove_newly_deleted([state])
+                return True
+        return False
+
+    def is_deleted(self, state):
+        """Return ``True`` if the given state is marked as deleted
+        within this uowtransaction."""
+
+        return state in self.states and self.states[state][0]
+
+    def memo(self, key, callable_):
+        if key in self.attributes:
+            return self.attributes[key]
+        else:
+            self.attributes[key] = ret = callable_()
+            return ret
+
+    def remove_state_actions(self, state):
+        """Remove pending actions for a state from the uowtransaction."""
+
+        isdelete = self.states[state][0]
+
+        self.states[state] = (isdelete, True)
+
+    def get_attribute_history(
+        self, state, key, passive=attributes.PASSIVE_NO_INITIALIZE
+    ):
+        """Facade to attributes.get_state_history(), including
+        caching of results."""
+
+        hashkey = ("history", state, key)
+
+        # cache the objects, not the states; the strong reference here
+        # prevents newly loaded objects from being dereferenced during the
+        # flush process
+
+        if hashkey in self.attributes:
+            history, state_history, cached_passive = self.attributes[hashkey]
+            # if the cached lookup was "passive" and now
+            # we want non-passive, do a non-passive lookup and re-cache
+
+            if (
+                not cached_passive & attributes.SQL_OK
+                and passive & attributes.SQL_OK
+            ):
+                impl = state.manager[key].impl
+                history = impl.get_history(
+                    state,
+                    state.dict,
+                    attributes.PASSIVE_OFF
+                    | attributes.LOAD_AGAINST_COMMITTED
+                    | attributes.NO_RAISE,
+                )
+                if history and impl.uses_objects:
+                    state_history = history.as_state()
+                else:
+                    state_history = history
+                self.attributes[hashkey] = (history, state_history, passive)
+        else:
+            impl = state.manager[key].impl
+            # TODO: store the history as (state, object) tuples
+            # so we don't have to keep converting here
+            history = impl.get_history(
+                state,
+                state.dict,
+                passive
+                | attributes.LOAD_AGAINST_COMMITTED
+                | attributes.NO_RAISE,
+            )
+            if history and impl.uses_objects:
+                state_history = history.as_state()
+            else:
+                state_history = history
+            self.attributes[hashkey] = (history, state_history, passive)
+
+        return state_history
+
+    def has_dep(self, processor):
+        return (processor, True) in self.presort_actions
+
+    def register_preprocessor(self, processor, fromparent):
+        key = (processor, fromparent)
+        if key not in self.presort_actions:
+            self.presort_actions[key] = Preprocess(processor, fromparent)
+
+    def register_object(
+        self,
+        state: InstanceState[Any],
+        isdelete: bool = False,
+        listonly: bool = False,
+        cancel_delete: bool = False,
+        operation: Optional[str] = None,
+        prop: Optional[MapperProperty] = None,
+    ) -> bool:
+        if not self.session._contains_state(state):
+            # this condition is normal when objects are registered
+            # as part of a relationship cascade operation.  it should
+            # not occur for the top-level register from Session.flush().
+            if not state.deleted and operation is not None:
+                util.warn(
+                    "Object of type %s not in session, %s operation "
+                    "along '%s' will not proceed"
+                    % (orm_util.state_class_str(state), operation, prop)
+                )
+            return False
+
+        if state not in self.states:
+            mapper = state.manager.mapper
+
+            if mapper not in self.mappers:
+                self._per_mapper_flush_actions(mapper)
+
+            self.mappers[mapper].add(state)
+            self.states[state] = (isdelete, listonly)
+        else:
+            if not listonly and (isdelete or cancel_delete):
+                self.states[state] = (isdelete, False)
+        return True
+
+    def register_post_update(self, state, post_update_cols):
+        mapper = state.manager.mapper.base_mapper
+        states, cols = self.post_update_states[mapper]
+        states.add(state)
+        cols.update(post_update_cols)
+
+    def _per_mapper_flush_actions(self, mapper):
+        saves = SaveUpdateAll(self, mapper.base_mapper)
+        deletes = DeleteAll(self, mapper.base_mapper)
+        self.dependencies.add((saves, deletes))
+
+        for dep in mapper._dependency_processors:
+            dep.per_property_preprocessors(self)
+
+        for prop in mapper.relationships:
+            if prop.viewonly:
+                continue
+            dep = prop._dependency_processor
+            dep.per_property_preprocessors(self)
+
+    @util.memoized_property
+    def _mapper_for_dep(self):
+        """return a dynamic mapping of (Mapper, DependencyProcessor) to
+        True or False, indicating if the DependencyProcessor operates
+        on objects of that Mapper.
+
+        The result is stored in the dictionary persistently once
+        calculated.
+
+        """
+        return util.PopulateDict(
+            lambda tup: tup[0]._props.get(tup[1].key) is tup[1].prop
+        )
+
+    def filter_states_for_dep(self, dep, states):
+        """Filter the given list of InstanceStates to those relevant to the
+        given DependencyProcessor.
+
+        """
+        mapper_for_dep = self._mapper_for_dep
+        return [s for s in states if mapper_for_dep[(s.manager.mapper, dep)]]
+
+    def states_for_mapper_hierarchy(self, mapper, isdelete, listonly):
+        checktup = (isdelete, listonly)
+        for mapper in mapper.base_mapper.self_and_descendants:
+            for state in self.mappers[mapper]:
+                if self.states[state] == checktup:
+                    yield state
+
+    def _generate_actions(self):
+        """Generate the full, unsorted collection of PostSortRecs as
+        well as dependency pairs for this UOWTransaction.
+
+        """
+        # execute presort_actions, until all states
+        # have been processed.   a presort_action might
+        # add new states to the uow.
+        while True:
+            ret = False
+            for action in list(self.presort_actions.values()):
+                if action.execute(self):
+                    ret = True
+            if not ret:
+                break
+
+        # see if the graph of mapper dependencies has cycles.
+        self.cycles = cycles = topological.find_cycles(
+            self.dependencies, list(self.postsort_actions.values())
+        )
+
+        if cycles:
+            # if yes, break the per-mapper actions into
+            # per-state actions
+            convert = {
+                rec: set(rec.per_state_flush_actions(self)) for rec in cycles
+            }
+
+            # rewrite the existing dependencies to point to
+            # the per-state actions for those per-mapper actions
+            # that were broken up.
+            for edge in list(self.dependencies):
+                if (
+                    None in edge
+                    or edge[0].disabled
+                    or edge[1].disabled
+                    or cycles.issuperset(edge)
+                ):
+                    self.dependencies.remove(edge)
+                elif edge[0] in cycles:
+                    self.dependencies.remove(edge)
+                    for dep in convert[edge[0]]:
+                        self.dependencies.add((dep, edge[1]))
+                elif edge[1] in cycles:
+                    self.dependencies.remove(edge)
+                    for dep in convert[edge[1]]:
+                        self.dependencies.add((edge[0], dep))
+
+        return {
+            a for a in self.postsort_actions.values() if not a.disabled
+        }.difference(cycles)
+
+    def execute(self) -> None:
+        postsort_actions = self._generate_actions()
+
+        postsort_actions = sorted(
+            postsort_actions,
+            key=lambda item: item.sort_key,
+        )
+        # sort = topological.sort(self.dependencies, postsort_actions)
+        # print "--------------"
+        # print "\ndependencies:", self.dependencies
+        # print "\ncycles:", self.cycles
+        # print "\nsort:", list(sort)
+        # print "\nCOUNT OF POSTSORT ACTIONS", len(postsort_actions)
+
+        # execute
+        if self.cycles:
+            for subset in topological.sort_as_subsets(
+                self.dependencies, postsort_actions
+            ):
+                set_ = set(subset)
+                while set_:
+                    n = set_.pop()
+                    n.execute_aggregate(self, set_)
+        else:
+            for rec in topological.sort(self.dependencies, postsort_actions):
+                rec.execute(self)
+
+    def finalize_flush_changes(self) -> None:
+        """Mark processed objects as clean / deleted after a successful
+        flush().
+
+        This method is called within the flush() method after the
+        execute() method has succeeded and the transaction has been committed.
+
+        """
+        if not self.states:
+            return
+
+        states = set(self.states)
+        isdel = {
+            s for (s, (isdelete, listonly)) in self.states.items() if isdelete
+        }
+        other = states.difference(isdel)
+        if isdel:
+            self.session._remove_newly_deleted(isdel)
+        if other:
+            self.session._register_persistent(other)
+
+
+class IterateMappersMixin:
+    __slots__ = ()
+
+    def _mappers(self, uow):
+        if self.fromparent:
+            return iter(
+                m
+                for m in self.dependency_processor.parent.self_and_descendants
+                if uow._mapper_for_dep[(m, self.dependency_processor)]
+            )
+        else:
+            return self.dependency_processor.mapper.self_and_descendants
+
+
+class Preprocess(IterateMappersMixin):
+    __slots__ = (
+        "dependency_processor",
+        "fromparent",
+        "processed",
+        "setup_flush_actions",
+    )
+
+    def __init__(self, dependency_processor, fromparent):
+        self.dependency_processor = dependency_processor
+        self.fromparent = fromparent
+        self.processed = set()
+        self.setup_flush_actions = False
+
+    def execute(self, uow):
+        delete_states = set()
+        save_states = set()
+
+        for mapper in self._mappers(uow):
+            for state in uow.mappers[mapper].difference(self.processed):
+                (isdelete, listonly) = uow.states[state]
+                if not listonly:
+                    if isdelete:
+                        delete_states.add(state)
+                    else:
+                        save_states.add(state)
+
+        if delete_states:
+            self.dependency_processor.presort_deletes(uow, delete_states)
+            self.processed.update(delete_states)
+        if save_states:
+            self.dependency_processor.presort_saves(uow, save_states)
+            self.processed.update(save_states)
+
+        if delete_states or save_states:
+            if not self.setup_flush_actions and (
+                self.dependency_processor.prop_has_changes(
+                    uow, delete_states, True
+                )
+                or self.dependency_processor.prop_has_changes(
+                    uow, save_states, False
+                )
+            ):
+                self.dependency_processor.per_property_flush_actions(uow)
+                self.setup_flush_actions = True
+            return True
+        else:
+            return False
+
+
+class PostSortRec:
+    __slots__ = ("disabled",)
+
+    def __new__(cls, uow, *args):
+        key = (cls,) + args
+        if key in uow.postsort_actions:
+            return uow.postsort_actions[key]
+        else:
+            uow.postsort_actions[key] = ret = object.__new__(cls)
+            ret.disabled = False
+            return ret
+
+    def execute_aggregate(self, uow, recs):
+        self.execute(uow)
+
+
+class ProcessAll(IterateMappersMixin, PostSortRec):
+    __slots__ = "dependency_processor", "isdelete", "fromparent", "sort_key"
+
+    def __init__(self, uow, dependency_processor, isdelete, fromparent):
+        self.dependency_processor = dependency_processor
+        self.sort_key = (
+            "ProcessAll",
+            self.dependency_processor.sort_key,
+            isdelete,
+        )
+        self.isdelete = isdelete
+        self.fromparent = fromparent
+        uow.deps[dependency_processor.parent.base_mapper].add(
+            dependency_processor
+        )
+
+    def execute(self, uow):
+        states = self._elements(uow)
+        if self.isdelete:
+            self.dependency_processor.process_deletes(uow, states)
+        else:
+            self.dependency_processor.process_saves(uow, states)
+
+    def per_state_flush_actions(self, uow):
+        # this is handled by SaveUpdateAll and DeleteAll,
+        # since a ProcessAll should unconditionally be pulled
+        # into per-state if either the parent/child mappers
+        # are part of a cycle
+        return iter([])
+
+    def __repr__(self):
+        return "%s(%s, isdelete=%s)" % (
+            self.__class__.__name__,
+            self.dependency_processor,
+            self.isdelete,
+        )
+
+    def _elements(self, uow):
+        for mapper in self._mappers(uow):
+            for state in uow.mappers[mapper]:
+                (isdelete, listonly) = uow.states[state]
+                if isdelete == self.isdelete and not listonly:
+                    yield state
+
+
+class PostUpdateAll(PostSortRec):
+    __slots__ = "mapper", "isdelete", "sort_key"
+
+    def __init__(self, uow, mapper, isdelete):
+        self.mapper = mapper
+        self.isdelete = isdelete
+        self.sort_key = ("PostUpdateAll", mapper._sort_key, isdelete)
+
+    @util.preload_module("sqlalchemy.orm.persistence")
+    def execute(self, uow):
+        persistence = util.preloaded.orm_persistence
+        states, cols = uow.post_update_states[self.mapper]
+        states = [s for s in states if uow.states[s][0] == self.isdelete]
+
+        persistence.post_update(self.mapper, states, uow, cols)
+
+
+class SaveUpdateAll(PostSortRec):
+    __slots__ = ("mapper", "sort_key")
+
+    def __init__(self, uow, mapper):
+        self.mapper = mapper
+        self.sort_key = ("SaveUpdateAll", mapper._sort_key)
+        assert mapper is mapper.base_mapper
+
+    @util.preload_module("sqlalchemy.orm.persistence")
+    def execute(self, uow):
+        util.preloaded.orm_persistence.save_obj(
+            self.mapper,
+            uow.states_for_mapper_hierarchy(self.mapper, False, False),
+            uow,
+        )
+
+    def per_state_flush_actions(self, uow):
+        states = list(
+            uow.states_for_mapper_hierarchy(self.mapper, False, False)
+        )
+        base_mapper = self.mapper.base_mapper
+        delete_all = DeleteAll(uow, base_mapper)
+        for state in states:
+            # keep saves before deletes -
+            # this ensures 'row switch' operations work
+            action = SaveUpdateState(uow, state)
+            uow.dependencies.add((action, delete_all))
+            yield action
+
+        for dep in uow.deps[self.mapper]:
+            states_for_prop = uow.filter_states_for_dep(dep, states)
+            dep.per_state_flush_actions(uow, states_for_prop, False)
+
+    def __repr__(self):
+        return "%s(%s)" % (self.__class__.__name__, self.mapper)
+
+
+class DeleteAll(PostSortRec):
+    __slots__ = ("mapper", "sort_key")
+
+    def __init__(self, uow, mapper):
+        self.mapper = mapper
+        self.sort_key = ("DeleteAll", mapper._sort_key)
+        assert mapper is mapper.base_mapper
+
+    @util.preload_module("sqlalchemy.orm.persistence")
+    def execute(self, uow):
+        util.preloaded.orm_persistence.delete_obj(
+            self.mapper,
+            uow.states_for_mapper_hierarchy(self.mapper, True, False),
+            uow,
+        )
+
+    def per_state_flush_actions(self, uow):
+        states = list(
+            uow.states_for_mapper_hierarchy(self.mapper, True, False)
+        )
+        base_mapper = self.mapper.base_mapper
+        save_all = SaveUpdateAll(uow, base_mapper)
+        for state in states:
+            # keep saves before deletes -
+            # this ensures 'row switch' operations work
+            action = DeleteState(uow, state)
+            uow.dependencies.add((save_all, action))
+            yield action
+
+        for dep in uow.deps[self.mapper]:
+            states_for_prop = uow.filter_states_for_dep(dep, states)
+            dep.per_state_flush_actions(uow, states_for_prop, True)
+
+    def __repr__(self):
+        return "%s(%s)" % (self.__class__.__name__, self.mapper)
+
+
+class ProcessState(PostSortRec):
+    __slots__ = "dependency_processor", "isdelete", "state", "sort_key"
+
+    def __init__(self, uow, dependency_processor, isdelete, state):
+        self.dependency_processor = dependency_processor
+        self.sort_key = ("ProcessState", dependency_processor.sort_key)
+        self.isdelete = isdelete
+        self.state = state
+
+    def execute_aggregate(self, uow, recs):
+        cls_ = self.__class__
+        dependency_processor = self.dependency_processor
+        isdelete = self.isdelete
+        our_recs = [
+            r
+            for r in recs
+            if r.__class__ is cls_
+            and r.dependency_processor is dependency_processor
+            and r.isdelete is isdelete
+        ]
+        recs.difference_update(our_recs)
+        states = [self.state] + [r.state for r in our_recs]
+        if isdelete:
+            dependency_processor.process_deletes(uow, states)
+        else:
+            dependency_processor.process_saves(uow, states)
+
+    def __repr__(self):
+        return "%s(%s, %s, delete=%s)" % (
+            self.__class__.__name__,
+            self.dependency_processor,
+            orm_util.state_str(self.state),
+            self.isdelete,
+        )
+
+
+class SaveUpdateState(PostSortRec):
+    __slots__ = "state", "mapper", "sort_key"
+
+    def __init__(self, uow, state):
+        self.state = state
+        self.mapper = state.mapper.base_mapper
+        self.sort_key = ("ProcessState", self.mapper._sort_key)
+
+    @util.preload_module("sqlalchemy.orm.persistence")
+    def execute_aggregate(self, uow, recs):
+        persistence = util.preloaded.orm_persistence
+        cls_ = self.__class__
+        mapper = self.mapper
+        our_recs = [
+            r for r in recs if r.__class__ is cls_ and r.mapper is mapper
+        ]
+        recs.difference_update(our_recs)
+        persistence.save_obj(
+            mapper, [self.state] + [r.state for r in our_recs], uow
+        )
+
+    def __repr__(self):
+        return "%s(%s)" % (
+            self.__class__.__name__,
+            orm_util.state_str(self.state),
+        )
+
+
+class DeleteState(PostSortRec):
+    __slots__ = "state", "mapper", "sort_key"
+
+    def __init__(self, uow, state):
+        self.state = state
+        self.mapper = state.mapper.base_mapper
+        self.sort_key = ("DeleteState", self.mapper._sort_key)
+
+    @util.preload_module("sqlalchemy.orm.persistence")
+    def execute_aggregate(self, uow, recs):
+        persistence = util.preloaded.orm_persistence
+        cls_ = self.__class__
+        mapper = self.mapper
+        our_recs = [
+            r for r in recs if r.__class__ is cls_ and r.mapper is mapper
+        ]
+        recs.difference_update(our_recs)
+        states = [self.state] + [r.state for r in our_recs]
+        persistence.delete_obj(
+            mapper, [s for s in states if uow.states[s][0]], uow
+        )
+
+    def __repr__(self):
+        return "%s(%s)" % (
+            self.__class__.__name__,
+            orm_util.state_str(self.state),
+        )