What should `python2` be for `faculty.clients.environment.Specification` now that Python 2 is not supported?

I am getting `faculty.clients.base.BadRequest: (, None, None)` when trying to create a new environment. Here is the spec ...

```python
from faculty.clients import environment

script = "echo hello"

spec = (
environment.Specification(
apt=environment.Apt(packages=[]),
bash=[environment.Script(script=script)],
python=environment.PythonSpecification(
python2=None,
python3=environment.PythonEnvironment(
pip=environment.Pip(extra_index_urls=[], packages=[]),
conda=environment.Conda(channels=[], packages=[]),
),
),
),
)

```

I think it may be due to the `python2` value. I pulled the schema from what I get from `client.get`. In the tests for this library though, this is not set to None as far as I can see. I also tried just setting it to the same value as for Python 3 and still got the same error. Perhaps this is because the Platform no longer supports Python 2 and this library has not been updated? I cannot see the Python 2 options on the UI btw.