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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def geodist(self, key, member1, member2, unit='m'):
 """Returns the distance between two members of a geospatial index. :rtype: list[float or None] """

        fut = self.execute(b'GEODIST', key, member1, member2, unit)
        return wait_convert(fut, make_geodist)