retval.update(evaled_operands[0])
retval = retval.intersection(evaled_operands[1])
elif self.op is Operation.INVERSION:
if len(evaled_operands) != 1:
retval.update(evaled_operands[0])
retval = retval.intersection(evaled_operands[1])
elif self.op is Operation.INVERSION:
if len(evaled_operands) != 1: