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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 footprint(self):
 """Return product footprint."""

        product_footprint = self._product_metadata.iter("Product_Footprint")
        # I don't know why two "Product_Footprint" items are found.
        for element in product_footprint:
            global_footprint = None
            for global_footprint in element.iter("Global_Footprint"):
                coords = global_footprint.findtext("EXT_POS_LIST").split()
                return _polygon_from_coords(coords)