def __getitem__(self, variable):
        assert isinstance(variable, Variable)

        intermediate = self.d[variable]
        while intermediate:
            try:
                intermediate = self.d[intermediate]
            except KeyError:
                return intermediate
Return stored element keys (as standard dicts)
dataset/ETHPy150Open nltk/nltk/nltk/inference/resolution.py/BindingDict.__getitem__--crossover with--dataset/ETHPy150Open rene-aguirre/pywinusb/pywinusb/hid/core.py/HidReport.keys