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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_combined_size(tiles):
 """Calculate combined size of tiles."""

    # TODO: Refactor calculating layout to avoid repetition.
    columns, rows = calc_columns_rows(len(tiles))
    tile_size = tiles[0].image.size
    return (tile_size[0] * columns, tile_size[1] * rows)