❯ cat > a.py
def fn(a, b, c, d, e):
    if a:
        ...
    try:
        ...
    except ValueError:
        ...
    if b:
        ...
    if c:
        ...
    if d:
        ...
    else:
        try:
            if a:
                if not b:
                    ...
        except ValueError:
            ...
    ...

❯ pip install ruff==0.0.246
Collecting ruff==0.0.246
  Using cached ruff-0.0.246-py3-none-macosx_10_9_x86_64.macosx_11_0_arm64.macosx_10_9_universal2.whl (10.7 MB)
Installing collected packages: ruff
  Attempting uninstall: ruff
    Found existing installation: ruff 0.0.244
    Uninstalling ruff-0.0.244:
      Successfully uninstalled ruff-0.0.244
Successfully installed ruff-0.0.246

❯ ruff --select C a.py
a.py:1:5: C901 `fn` is too complex (11)
Found 1 error.

❯ pip install ruff==0.0.247
Collecting ruff==0.0.247
  Using cached ruff-0.0.247-py3-none-macosx_10_9_x86_64.macosx_11_0_arm64.macosx_10_9_universal2.whl (11.1 MB)
Installing collected packages: ruff
  Attempting uninstall: ruff
    Found existing installation: ruff 0.0.246
    Uninstalling ruff-0.0.246:
      Successfully uninstalled ruff-0.0.246
Successfully installed ruff-0.0.247

❯ ruff --select C a.py
❯