code: def p_conditional_expr(self, p):
          
          if len(p) == 2:
              p[0] = p[1]
          else:
              p[0] = self.asttypes.Conditional(
                  predicate=p[1], consequent=p[3], alternative=p[5])
              p[0].setpos(p, 2)
docs: conditional_expr \
              : logical_or_expr
              | logical_or_expr CONDOP assignment_expr COLON assignment_expr