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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 chk(self, annotations, fout_err):
 """Check annotations."""

        for idx, ntd in enumerate(annotations):
            self._chk_fld(ntd, "Qualifier")        # optional 0 or greater
            self._chk_fld(ntd, "DB_Reference", 1)  # required 1 or greater
            self._chk_fld(ntd, "With_From")        # optional 0 or greater
            self._chk_fld(ntd, "DB_Name", 0, 1)    # optional 0 or 1
            self._chk_fld(ntd, "DB_Synonym")       # optional 0 or greater
            self._chk_fld(ntd, "Taxon", 1, 2)
            flds = list(ntd)
            self._chk_qty_eq_1(flds)
            # self._chk_qualifier(ntd.Qualifier, flds, idx)
            if not ntd.Taxon or len(ntd.Taxon) not in {1, 2}:
                self.illegal_lines['BAD TAXON'].append((idx, '**{I}) TAXON: {NT}'.format(I=idx, NT=ntd)))
        if self.illegal_lines:
            self.prt_error_summary(fout_err)
        return not self.illegal_lines