Fixup: update function name in docs to match source

[jayaddison]

Considerations to bear in mind when deciding whether to rename this function:

• It has recently been renamed (neither a plus nor minus for renaming again, necessarily)
• It is a public method, by naming convention (makes renaming it slightly less attractive)
• It refers in a strict-ish sense to right-hand-side line splits (so perhaps it could be renamed further; this is mitigated by a variable rename)

Resolves #1996

[ichard26]

I mean, I'm not 100% approving this, but since we don't provide a stable Python API, modifying internals like this is fair game IMO. Other core team members may have a different viewpoint.

[JelleZijlstra]

Sounds like we should at least do this to unbreak the docs build?

[ichard26]

Sounds like we should at least do this to unbreak the docs build?

Yeah I agree on second thought, somehow I ignored that was failing and this is the fix.