builtin_predicate.py 文件源码

def ast(self):
        """Python AST of this predicate (construct transitively for all indirect children as well).

        :return: AST of describing all children predicates
        """
        # We should return:
        #   return ast.NameConstant(value=True)
        # but it does not work with codegen
        return ast.Name(id='True', ctx=ast.Load())