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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 unsigned_hex_to_signed_int(hex_string: str) -> int: """Converts a 64-bit hex string to a signed int value. This is due to the fact that Apache Thrift only has signed values. Examples: '17133d482ba4f605' => 1662740067609015813 'b6dbb1c2b362bf51' => -5270423489115668655 :param hex_string: the string representation of a zipkin ID :returns: signed int representation """

    v = struct.unpack(
        'q', struct.pack('Q', int(hex_string, 16)))[0]  # type: int
    return v