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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 slice_cardinal(self, key):
 """ Get the slice of this object by the value or values of the cardinal dimension. """

        cls = self.__class__
        key = check_key(self, key, cardinal=True)
        return cls(self[self[self._cardinal[0]].isin(key)])