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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 _calculate_edges(self):
 """Calculate edges of the current label. Not intended for external use. """

        # Calculate the left edge of the label.
        left = self.specs.left_margin
        left += (self.specs.label_width * (self._position[1] - 1))
        if self.specs.column_gap:
            left += (self.specs.column_gap * (self._position[1] - 1))
        left *= mm

        # And the bottom.
        bottom = self.specs.sheet_height - self.specs.top_margin
        bottom -= (self.specs.label_height * self._position[0])
        if self.specs.row_gap:
            bottom -= (self.specs.row_gap * (self._position[0] - 1))
        bottom *= mm

        # Done.
        return float(left), float(bottom)