'Calculates the md5 hash of a given string
:example \'cfcd208495d565ef66e7dff9f98764da\''

@classmethod
def md5(cls, raw_output=False):

    res = hashlib.md5(str(random.random()).encode(u'utf-8'))
    if raw_output:
        return res.digest()
    return res.hexdigest()
