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)
Returns the distance between two members of a geospatial index.

        :rtype: list[float or None]