@utils.check_messages("<STR_LIT>")<EOL><INDENT>def visit_dict(self, node):<DEDENT>
keys = set()<EOL>for k, _ in node.items:<EOL><INDENT>if isinstance(k, astroid.Const):<EOL><INDENT>key = k.value<EOL>if key in keys:<EOL><INDENT>self.add_message("<STR_LIT>", node=node, args=key)<EOL><DEDENT>keys.add(key)<EOL><DEDENT><DEDENT>
check duplicate key in dictionary