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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_label_or_level_reference(self, key, axis=0):
 """ Test whether a key is a label or level reference for a given axis. To be considered either a label or a level reference, `key` must be a string that: - (axis=0):
 Matches a column label or an index level - (axis=1):
 Matches an index label or a column level Parameters key: str Potential label or level name axis: int, default 0 Axis that levels are associated with (0 for index, 1 for columns) Returns ------- is_label_or_level: bool """


        if self.ndim > 2:
            raise NotImplementedError(
                "_is_label_or_level_reference is not implemented for {type}"
                .format(type=type(self)))

        return (self._is_level_reference(key, axis=axis) or
                self._is_label_reference(key, axis=axis))