## Summary
Per https://github.com/astral-sh/ruff/issues/9570:
> `dtype` are a bit of a strange beast, but definitely best thought of
as instances, not classes, and they are meant to be comparable not just
to their own class, but also to the corresponding scalar types (e.g.,
`x.dtype == np.float32`) and strings (e.g., `x.dtype == ['i1,i4']`;
basically, `__eq__` always tries to do `dtype(other)`.
This PR thus allows comparisons to `dtype` in preview.
Closes https://github.com/astral-sh/ruff/issues/9570.
## Test Plan
`cargo test`
## Summary
Adds `memoryview` to the list of typeclasses that `fn is_type()` uses
for type comparison checks so that it raises a violation if `is`, `is
not` or `isinstance()` are not used.
## Test Plan
Added examples to existing fixture
## Issue Link
Closes: https://github.com/astral-sh/ruff/issues/8483
## Summary
This PR updates our E721 implementation and semantics to match the
updated `pycodestyle` logic, which I think is an improvement.
Specifically, we now allow `type(obj) is int` for exact type
comparisons, which were previously impossible. So now, we're largely
just linting against code like `type(obj) == int`.
This change is gated to preview mode.
Closes https://github.com/astral-sh/ruff/issues/7904.
## Test Plan
Updated the test fixture and ensured parity with latest Flake8.