def __setitem__(self, key, value, dict_setitem=dict.__setitem__):
        # Setting a new item creates a new link which goes at the end of the
        # linked list, and the inherited dictionary is updated with the new
        # key/value pair.
        if key not in self:
            root = self.__root
            last = root[0]
            last[1] = root[0] = self.__map[key] = [last, root, key]
        dict_setitem(self, key, value)
Returns true if this object is a tree.
dataset/ETHPy150Open PythonCharmers/python-future/docs/3rd-party-py3k-compat-code/pandas_py3k.py/_OrderedDict.__setitem__--crossover with--dataset/ETHPy150Open Djacket/djacket/core/backend/git/object.py/GitObject.is_tree