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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_left_key_rect(self):
 """Returns tuple key rect of left cell"""


        key_left = self.row, self.col - 1, self.tab

        border_width_right = \
            float(self.cell_attributes[key_left]["borderwidth_right"]) / 2.0

        rect_left = (self.x-border_width_right, self.y,
                     border_width_right, self.height)
        return key_left, rect_left