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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 _center_tile(self, position, size):
 x, y = position w, h = size """Calculate the centre of a tile given the top-left corner and the size of the image."""

        return x + (self.cell_width - w) / 2, y + (self.cell_height - h) / 2