pyupgrade.py 文件源码

def visit_Call(self, node):
        if (
                isinstance(node.func, ast.Name) and
                node.func.id == 'dict' and
                len(node.args) == 1 and
                not _has_kwargs(node) and
                isinstance(node.args[0], (ast.ListComp, ast.GeneratorExp)) and
                isinstance(node.args[0].elt, (ast.Tuple, ast.List)) and
                len(node.args[0].elt.elts) == 2
        ):
            arg, = node.args
            key = Offset(node.func.lineno, node.func.col_offset)
            self.dicts[key] = arg
        self.generic_visit(node)