But doing such string replacement is not safe. json.dumps () is widely used in Python server, so I'm wondering if anyone faces such issues? Are there any ways to directly parse the above Json format, ...

dumps - Fast JSON Serialization with Rust A Python library that uses Rust for fast JSON serialization of Python objects.

It's in the name, after all. edit: I see you're using json.dump (sorry, I didn't really read your post carefully before jumping straight in to make a reply ).