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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 _parse_multi_byte(self, s):
 # type: (str) -> int """ _parse_multi_byte parses x as a multibyte representation to get the int value of this AbstractUVarIntField. @param str s: the multibyte string to parse. @return int: The parsed int value represented by this AbstractUVarIntField. # noqa: E501 @raise: AssertionError @raise: Scapy_Exception if the input value encodes an integer larger than 1<<64 # noqa: E501 """


        assert(len(s) >= 2)

        tmp_len = len(s)

        value = 0
        i = 1
        byte = orb(s[i])
        # For CPU sake, stops at an arbitrary large number!
        max_value = 1 << 64
        # As long as the MSG is set, an another byte must be read
        while byte & 0x80:
            value += (byte ^ 0x80) << (7 * (i - 1))
            if value > max_value:
                raise error.Scapy_Exception(
                    'out-of-bound value: the string encodes a value that is too large (>2^{64}): {}'.format(value)  # noqa: E501
                )
            i += 1
            assert i < tmp_len, 'EINVAL: x: out-of-bound read: the string ends before the AbstractUVarIntField!'  # noqa: E501
            byte = orb(s[i])
        value += byte << (7 * (i - 1))
        value += self._max_value

        assert(value >= 0)
        return value