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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 _pretty_size(size):
    '''
    Print sizes in a similar fashion as eclean
    '''
    units = [' G', ' M', ' K', ' B']
    while units and size >= 1000:
        size = size / 1024.0
        units.pop()
    return '{0}{1}'.format(round(size, 1), units[-1])