LGTM.com - false positive – too pedantic on Python structural typing / Protocol

LGTM is overly pedantic with Python's ``typing.Protocol``, i.e. structural typing, expecting it to be complete like a regular class.

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A ``Protocol`` is often used for type-hints of the *minimum* required functionality. In the false positive, a ``Protocol`` is used to express "can be compared by ``<``"; this is the minimum required to allow sorting:

> [The sort algorithm uses only `<` comparisons between items.](https://docs.python.org/3/library/functions.html#sorted)

> [The sort routines are guaranteed to use `__lt__()` when making comparisons between two objects.](https://docs.python.org/3/howto/sorting.html#odd-and-ends)

So the entire purpose of the ``Protocol`` is just to express the *minimum* not *complete* functionality.

LGTM instead treats this ``Protocol`` as a regular class and warns because it expects the *complete* set of comparison operators.

https://lgtm.com/projects/g/maxfischer2781/asyncstdlib/snapshot/cac1578bed589b6d1d858ec05441edb1a9756407/files/asyncstdlib/_typing.py?sort=name&dir=ASC&mode=heatmap#x5f23fe7abe3304d0:1