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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 get_id2gos(self, **kws):
 #### def get_annotations_dct(self, taxid, options):
 """Return geneid2gos, or optionally go2geneids."""

        if len(self.taxid2asscs) == 1:
            taxid = next(iter(self.taxid2asscs.keys()))
            return self._get_id2gos(self.taxid2asscs[taxid], **kws)
        assert 'taxid' in kws, "**FATAL: 'taxid' NOT FOUND IN Gene2GoReader::get_id2gos({KW})".format(KW=kws)
        taxid = kws['taxid']
        assert taxid in self.taxid2asscs, '**FATAL: TAXID({T}) DATA MISSING'.format(T=taxid)
        return self._get_id2gos(self.taxid2asscs[taxid], **kws)