from UserDict import DictMixin
class odict(DictMixin):
def __init__(self):
self._keys = []
self._data = {}
def __setitem__(self, key, value):
if key not in self._data:
self._keys.append(key)
self._data[key] = value
def __getitem__(self, key):
return self._data[key]
def __delitem__(self, key):
del self._data[key]
self._keys.remove(key)
def keys(self):
return list(self._keys)
def copy(self):
copyDict = odict()
copyDict._data = self._data.copy()
copyDict._keys = self._keys[:]
return copyDict