flake8 check

[cxhernandez]

Mostly aesthetics, but lines like this seemed incorrect:

if not field in self_cls.fields:

Any reason why it's not this?

if field not in self_cls.fields:

[peastman]

They're synonymous. Think of it as if not (field in self_cls.fields).

[cxhernandez]

Ohhh— thanks! I was thinking not would be executed before in.

[mpharrigan]

The latter might be faster? it can short circuit

[peastman]

I don't think there would be any difference. Determining whether something is in a container is identical to determining whether it is not in the container. The only difference is inverting the return value.

[mpharrigan]

doh!