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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_dimensions(image, long_side, short_side):
 """Returns the thumbnail dimensions depending on the images format."""

    if image.width >= image.height:
        return '{0}x{1}'.format(long_side, short_side)
    return '{0}x{1}'.format(short_side, long_side)