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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 check_passwd(guess, passwd):
 """ Tests to see if the guess, after salting and hashing, matches the passwd from the database. @param guess: incoming password trying to be used for authentication @param passwd: already encrypted password from the database @returns: boolean """

    m = sha1()
    salt = passwd[:salt_len * 2]  # salt_len * 2 due to encode('hex_codec')
    m.update(unicode2bytes(guess) + unicode2bytes(salt))
    crypted_guess = bytes2unicode(salt) + m.hexdigest()

    return (crypted_guess == bytes2unicode(passwd))