Indeed, and that's through the API. If you use Claude Chat/Code and even if you then turn off web search, it still has access to some of its tools (for doing calculations, running small code snippets etc.) and that environment contains chardets code 4 times:
It's not surprising that they were able to create a new, working version of chardet this quickly. It seems the author just told Claude Code to "do a clean room implementation" and to make sure the code looks different from the original chardet (named several times in the prompt) without considering the training set and the tendency for LLMs to "cheat".
https://github.com/chardet/chardet/blob/5.0.0/chardet/mbchar...