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# Backport of OrderedDict() class that runs on Python 2.4, 2.5, 2.6, 2.7 and pypy.
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# Passes Python2.7's test suite and incorporates all the latest updates.
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# Created by Raymond Hettinger on Wed, 18 Mar 2009 (MIT License)
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from thread import get_ident as _get_ident
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from dummy_thread import get_ident as _get_ident
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from _abcoll import KeysView, ValuesView, ItemsView
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class OrderedDict(dict):
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'Dictionary that remembers insertion order'
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# An inherited dict maps keys to values.
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# The inherited dict provides __getitem__, __len__, __contains__, and get.
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# The remaining methods are order-aware.
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# Big-O running times for all methods are the same as for regular dictionaries.
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# The internal self.__map dictionary maps keys to links in a doubly linked list.
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# The circular doubly linked list starts and ends with a sentinel element.
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# The sentinel element never gets deleted (this simplifies the algorithm).
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# Each link is stored as a list of length three: [PREV, NEXT, KEY].
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def __init__(self, *args, **kwds):
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'''Initialize an ordered dictionary. Signature is the same as for
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regular dictionaries, but keyword arguments are not recommended
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because their insertion order is arbitrary.
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raise TypeError('expected at most 1 arguments, got %d' % len(args))
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except AttributeError:
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self.__root = root = [] # sentinel node
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root[:] = [root, root, None]
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self.__update(*args, **kwds)
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def __setitem__(self, key, value, dict_setitem=dict.__setitem__):
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'od.__setitem__(i, y) <==> od[i]=y'
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# Setting a new item creates a new link which goes at the end of the linked
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# list, and the inherited dictionary is updated with the new key/value pair.
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last[1] = root[0] = self.__map[key] = [last, root, key]
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dict_setitem(self, key, value)
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def __delitem__(self, key, dict_delitem=dict.__delitem__):
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'od.__delitem__(y) <==> del od[y]'
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# Deleting an existing item uses self.__map to find the link which is
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# then removed by updating the links in the predecessor and successor nodes.
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dict_delitem(self, key)
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link_prev, link_next, key = self.__map.pop(key)
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link_prev[1] = link_next
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link_next[0] = link_prev
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'od.__iter__() <==> iter(od)'
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while curr is not root:
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def __reversed__(self):
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'od.__reversed__() <==> reversed(od)'
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while curr is not root:
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'od.clear() -> None. Remove all items from od.'
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for node in self.__map.itervalues():
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root[:] = [root, root, None]
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except AttributeError:
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def popitem(self, last=True):
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'''od.popitem() -> (k, v), return and remove a (key, value) pair.
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Pairs are returned in LIFO order if last is true or FIFO order if false.
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raise KeyError('dictionary is empty')
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value = dict.pop(self, key)
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# -- the following methods do not depend on the internal structure --
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'od.keys() -> list of keys in od'
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'od.values() -> list of values in od'
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return [self[key] for key in self]
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'od.items() -> list of (key, value) pairs in od'
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return [(key, self[key]) for key in self]
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'od.iterkeys() -> an iterator over the keys in od'
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def itervalues(self):
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'od.itervalues -> an iterator over the values in od'
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'od.iteritems -> an iterator over the (key, value) items in od'
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def update(*args, **kwds):
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'''od.update(E, **F) -> None. Update od from dict/iterable E and F.
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If E is a dict instance, does: for k in E: od[k] = E[k]
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If E has a .keys() method, does: for k in E.keys(): od[k] = E[k]
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Or if E is an iterable of items, does: for k, v in E: od[k] = v
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In either case, this is followed by: for k, v in F.items(): od[k] = v
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raise TypeError('update() takes at most 2 positional '
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'arguments (%d given)' % (len(args),))
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raise TypeError('update() takes at least 1 argument (0 given)')
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# Make progressively weaker assumptions about "other"
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if isinstance(other, dict):
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self[key] = other[key]
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elif hasattr(other, 'keys'):
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for key in other.keys():
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self[key] = other[key]
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for key, value in other:
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for key, value in kwds.items():
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__update = update # let subclasses override update without breaking __init__
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def pop(self, key, default=__marker):
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'''od.pop(k[,d]) -> v, remove specified key and return the corresponding value.
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If key is not found, d is returned if given, otherwise KeyError is raised.
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if default is self.__marker:
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def setdefault(self, key, default=None):
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'od.setdefault(k[,d]) -> od.get(k,d), also set od[k]=d if k not in od'
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def __repr__(self, _repr_running={}):
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'od.__repr__() <==> repr(od)'
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call_key = id(self), _get_ident()
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if call_key in _repr_running:
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_repr_running[call_key] = 1
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return '%s()' % (self.__class__.__name__,)
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return '%s(%r)' % (self.__class__.__name__, self.items())
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del _repr_running[call_key]
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def __reduce__(self):
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'Return state information for pickling'
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items = [[k, self[k]] for k in self]
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inst_dict = vars(self).copy()
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for k in vars(OrderedDict()):
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inst_dict.pop(k, None)
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return (self.__class__, (items,), inst_dict)
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return self.__class__, (items,)
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'od.copy() -> a shallow copy of od'
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return self.__class__(self)
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def fromkeys(cls, iterable, value=None):
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'''OD.fromkeys(S[, v]) -> New ordered dictionary with keys from S
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and values equal to v (which defaults to None).
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def __eq__(self, other):
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'''od.__eq__(y) <==> od==y. Comparison to another OD is order-sensitive
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while comparison to a regular mapping is order-insensitive.
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if isinstance(other, OrderedDict):
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return len(self)==len(other) and self.items() == other.items()
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return dict.__eq__(self, other)
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def __ne__(self, other):
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return not self == other
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# -- the following methods are only used in Python 2.7 --
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"od.viewkeys() -> a set-like object providing a view on od's keys"
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return KeysView(self)
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def viewvalues(self):
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"od.viewvalues() -> an object providing a view on od's values"
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return ValuesView(self)
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"od.viewitems() -> a set-like object providing a view on od's items"
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return ItemsView(self)