noxfile.py (6 lines of code) (raw):
import nox
@nox.session(reuse_venv=True, name="test-pydantic-v1")
def test_pydantic_v1(session: nox.Session) -> None:
session.install("-r", "requirements-dev.lock")
session.install("pydantic<2")
session.run("pytest", "--showlocals", "--ignore=tests/functional", *session.posargs)