langchain/client/langchain.py/LangChainPlusClient/_repr_html_
class LangChainPlusClient:    def _repr_html_(self) -> str:
        """Return an HTML representation of the instance with a link to the URL."""
        if _is_localhost(self.api_url):
            link = "http://localhost"
        elif "dev" in self.api_url:
            link = "https://dev.langchain.plus"
        else:
            link = "https://www.langchain.plus"
        return f'<a href="{link}", target="_blank" rel="noopener">LangChain+ Client</a>'