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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_reference(self, key, axis=0):
 """ Test whether a key is a label reference for a given axis. To be considered a label reference, `key` must be a string that: - (axis=0):
 Matches a column label - (axis=1):
 Matches an index label Parameters key: str Potential label name axis: int, default 0 Axis perpendicular to the axis that labels are associated with (0 means search for column labels, 1 means search for index labels) Returns ------- is_label: bool """

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

        axis = self._get_axis_number(axis)
        other_axes = (ax for ax in range(self._AXIS_LEN) if ax != axis)

        return (key is not None and
                is_hashable(key) and
                any(key in self.axes[ax] for ax in other_axes))