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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 check_sizes(size, width, height):
 """ Check that these arguments, in supplied, are consistent. Return a (width, height) pair. """

    if not size:
        return width, height

    if len(size) != 2:
        raise ValueError(
          "size argument should be a pair (width, height)")
    if width is not None and width != size[0]:
        raise ValueError(
          "size[0] (%r) and width (%r) should match when both are used."
          % (size[0], width))
    if height is not None and height != size[1]:
        raise ValueError(
          "size[1] (%r) and height (%r) should match when both are used."
          % (size[1], height))
    return size