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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 human_size(bytes, units=[' bytes','KB','MB','GB','TB', 'PB', 'EB']):
 """ Returns a human readable string reprentation of bytes"""

    return str(bytes) + units[0] if bytes < 1024 else human_size(bytes>>10, units[1:])