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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 _iget_item_cache(self, item):
 """Return the cached item, item represents a positional indexer."""

        ax = self._info_axis
        if ax.is_unique:
            lower = self._get_item_cache(ax[item])
        else:
            lower = self._take(item, axis=self._info_axis_number)
        return lower