DeprecationWarning: Inheritance class AiohttpClientSession from ClientSession is discouraged

[sdediu00]

Environment details

• Programming language: Python
• OS: Ubuntu 24.04.3 LTS
• Language runtime version: 3.13.11
• Package version: 1.60.0

Steps to reproduce

1. Have warnings.filterwarnings("error") so that they get raised
2. Execute the following code

    warnings.filterwarnings("error")

    gemini = Client(api_key=config_lookup("RANDOM_KEY"))
    response = asyncio.run(
        gemini.aio.models.generate_content(
            model="gemini-2.5-flash",
            contents="What is the capital of France?",
            config=types.GenerateContentConfig(
                thinking_config=types.ThinkingConfig(thinking_budget=0),  # Disables thinking
            ),
        )
    )

    print(response)

3. The following will get raised DeprecationWarning: Inheritance class AiohttpClientSession from ClientSession is discouraged

In our development environment, we also make sure to raise warnings as errors since we want to be aware of possible issues, like the one mentioned above.

As far as I can see, this particular Deprecation seems to have been in effect from 2018, issue here

For now our fix was to ignore the error, but it would probably be best to take care of it.