ftplib: Correct timeout option to float | None

[heavywatal]

It is more consistent with the official document.
https://docs.python.org/3/library/ftplib.html

[AlexWaygood]

Thanks! From skimming the source code of the runtime version of this module, I think you may be correct that None is acceptable. However, I think we should use float | None instead of int | None. Type annotations were only added to the official docs a few weeks ago, and it looks like they didn't mean to imply that passing a float is incorrect. See the conversation at python/cpython#114359 (comment)

[heavywatal]

Thank you for the prompt feedback! Modified them to float | None accordingly.

[github-actions]

According to mypy_primer, this change has no effect on the checked open source code. 🤖🎉

[AlexWaygood]

Thanks!

[AlexWaygood]

Agree that this could be None -- the implementation specifically checks to see whether or not it's None: https://github.com/python/cpython/blob/46245b0d831b9f5b15b4a0483c785ea71bffef12/Lib/ftplib.py#L153-L154

[AlexWaygood]

The timeout value is also eventually passed to socket.create_connection here: https://github.com/python/cpython/blob/46245b0d831b9f5b15b4a0483c785ea71bffef12/Lib/ftplib.py#L158-L159

And our annotations for create_connection state that None is accepted:

typeshed/stdlib/socket.pyi

Lines 803 to 815 in 4124569

	if sys.version_info >= (3, 11):
	def create_connection(
	address: tuple[str | None, int],
	timeout: float | None = ..., # noqa: F811
	source_address: _Address | None = None,
	*,
	all_errors: bool = False,
	) -> socket: ...
	else:
	def create_connection(
	address: tuple[str | None, int], timeout: float | None = ..., source_address: _Address | None = None # noqa: F811
	) -> socket: ...