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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 unpack(self, unpacker):
 """ unpack this instance with data from unpacker """


        (a, b, c, d) = unpacker.unpack_struct(_HHHH)

        self.inner_info_ref = a
        self.outer_info_ref = b
        self.name_ref = c
        self.access_flags = d