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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 signed_int_to_unsigned_hex(signed_int: int) -> str: """Converts a signed int value to a 64-bit hex string. Examples: 1662740067609015813 => '17133d482ba4f605' -5270423489115668655 => 'b6dbb1c2b362bf51' :param signed_int: an int to convert :returns: unsigned hex string """

    hex_string = hex(struct.unpack('Q', struct.pack('q', signed_int))[0])[2:]
    if hex_string.endswith('L'):
        return hex_string[:-1]
    return hex_string