def prepack(self, namedstruct, skip_self=False, skip_sub=False):
        '''
        Run prepack
        '''
        if not skip_sub and self.header is not None and hasattr(self.header, 'fullprepack'):
            self.header.fullprepack(namedstruct._seqs[0])
        Parser.prepack(self, namedstruct, skip_self, skip_sub)
Run prepack