A simple bidirectional dictionary.
Implements a 1:1 dictionary.
It implies that two keys can't have the same value.
>>> relation = bidict()
>>> relation['Alice'] = 'Bob'
>>> print(relation['Bob'])
>>> 'Alice'
>>> print(relation['Alice'])
>>> 'Bob'
def __init__(self, *args, **kwargs):
super(bidict, self).__init__(*args, **kwargs)
inverse = dict()
for key in self:
inverse[self[key]] = key
self.update(inverse)
def __setitem__(self, key, value):
if key in self:
del self[key]
super(bidict, self).__setitem__(key, value)
super(bidict, self).__setitem__(value, key)
def __delitem__(self, key):
value = self[key]
super(bidict, self).__delitem__(key)
super(bidict, self).__delitem__(value)