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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 crypt_salt_is_valid(salt):
 """ Validate a salt as crypt salt :param str salt: a password salt :return: ``True`` if ``salt`` is a valid crypt salt on this system, ``False`` otherwise :rtype: bool """

    if len(salt) < 2:
        return False
    else:
        if salt[0] == '$':
            if salt[1] == '$':
                return False
            else:
                if '$' not in salt[1:]:
                    return False
                else:
                    hashed = crypt.crypt("", salt)
                    if not hashed or '$' not in hashed[1:]:
                        return False
                    else:
                        return True
        else:
            return True