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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 bytes2uuid(b):
 """ Return standard human-friendly UUID. """

    if b.strip(chr(0)) == '':
        return None

    s = b.encode('hex')
    return "%s-%s-%s-%s-%s" % (s[0:8], s[8:12], s[12:16], s[16:20], s[20:])