def g_to_n(self, g_interval):
grs, gre = g_interval.start.base - <NUM_LIT:1> - self.gc_offset, g_interval.end.base - <NUM_LIT:1> - self.gc_offset<EOL>frs, frs_offset, frs_cigar = self._map(<EOL>from_pos=self.ref_pos, to_pos=self.tgt_pos, pos=grs, base="<STR_LIT:start>")<EOL>fre, fre_offset, fre_cigar = self._map(<EOL>from_pos=self.ref_pos, to_pos=self.tgt_pos, pos=gre, base="<STR_LIT:end>")<EOL>if self.strand == -<NUM_LIT:1>:<EOL><INDENT>frs, fre = self.tgt_len - fre - <NUM_LIT:1>, self.tgt_len - frs - <NUM_LIT:1><EOL>frs_offset, fre_offset = -fre_offset, -frs_offset<EOL><DEDENT>return hgvs.location.BaseOffsetInterval(<EOL>start=hgvs.location.BaseOffsetPosition(<EOL>base=frs + <NUM_LIT:1>, offset=frs_offset, datum=Datum.SEQ_START),<EOL>end=hgvs.location.BaseOffsetPosition(<EOL>base=fre + <NUM_LIT:1>, offset=fre_offset, datum=Datum.SEQ_START),<EOL>uncertain=frs_cigar in '<STR_LIT>' or fre_cigar in '<STR_LIT>')<EOL>
convert a genomic (g.) interval to a transcript cDNA (n.) interval