def merge_by_adding_new_alts(self, other, ref_seq):
if self.CHROM != other.CHROM:<EOL><INDENT>raise Error('<STR_LIT>' + str(self) + '<STR_LIT:\n>' + str(other))<EOL><DEDENT>new_ref_start = min(self.POS, other.POS)<EOL>new_ref_end = max(self.ref_end_pos(), other.ref_end_pos())<EOL>new_ref_end = min(new_ref_end, len(ref_seq) - <NUM_LIT:1>)<EOL>other = copy.copy(other)<EOL>self.add_flanking_seqs(ref_seq, new_ref_start, new_ref_end)<EOL>other.add_flanking_seqs(ref_seq, new_ref_start, new_ref_end)<EOL>for other_alt in other.ALT:<EOL><INDENT>if other_alt not in self.ALT:<EOL><INDENT>self.ALT.append(other_alt)<EOL><DEDENT><DEDENT>
Adds other VcfRecord to this one, by adding new field(s) in the ALT
        column. Also adds REF nucleotides if they are needed. eg:
        ref: ACGT
        this var: pos=3, REF=T, ALT=A
        other var: pos=1, REF=C, ALT=T
        will change this var to be pos=1, REF=CGT, ALT=TGT,CGA