Using compiles leads to untyped decorator

[kasium]

Describe the bug
The compile decorator is not fully typed. Therefore mypy complains when using it

Expected behavior
Mypy doesn't complain

To Reproduce
Use compile as a decorator

Error

error: Untyped decorator makes function "foo" untyped  [misc]

Versions.

• OS: Linux
• Python: 3.7.1
• SQLAlchemy: 1.4.41
• mypy: 0.982
• SQLAlchemy2-stubs: 0.0.2a29

I'm happy to give a PR a try

[verhovensky]

Facing same issue

@compiles(Utcnow, 'postgresql')
def pg_utcnow(element, compiler, **kw):
    return "TIMEZONE('utc', CURRENT_TIMESTAMP)"


@compiles(Utcnow, 'mssql')
def ms_utcnow(element, compiler, **kw):
    return 'GETUTCDATE()'