def called_alts_from_genotype(self):
if '<STR_LIT>' not in self.FORMAT:<EOL><INDENT>return None<EOL><DEDENT>genotype_indexes = set([int(x) for x in self.FORMAT['<STR_LIT>'].split('<STR_LIT:/>')])<EOL>alts = set()<EOL>for i in genotype_indexes:<EOL><INDENT>if i == <NUM_LIT:0>:<EOL><INDENT>alts.add(self.REF)<EOL><DEDENT>else:<EOL><INDENT>alts.add(self.ALT[i-<NUM_LIT:1>])<EOL><DEDENT><DEDENT>return alts<EOL>
Returns a set of the (maybe REF and) ALT strings that were called, using GT in FORMAT.
        Returns None if GT not in the record