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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 is_(self, other):
 """ More flexible, faster check like ``is`` but that works through views. Note: this is *not* the same as ``Index.identical()``, which checks that metadata is also the same. Parameters other : object other object to compare against. Returns ------- True if both have same underlying data, False otherwise : bool """

        # use something other than None to be clearer
        return self._id is getattr(
            other, '_id', Ellipsis) and self._id is not None