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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 get_merging_cell(self, key):
 """Returns key of cell that merges the cell key or None if cell key not merged Parameters key: 3-tuple of Integer \tThe key of the cell that is merged """


        row, col, tab = key

        # Is cell merged
        merge_area = self[key]["merge_area"]

        if merge_area:
            return merge_area[0], merge_area[1], tab