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I'm using mypy in my python project for type checking. I'm also using PyYAML for reading and writing the project configuration files. Unfortunately, when using the recommended import mechanism from the PyYAML documentation this generates a spurious error in a try/except clause that attempts to import native libraries:

from yaml import load, dump
    from yaml import CLoader as Loader, CDumper as Dumper
except ImportError:
    from yaml import Loader, Dumper
On my system CLoader and CDumper aren't present, which results in the errors error: Module 'yaml' has no attribute 'CLoader' and error: Module 'yaml' has no attribute 'CDumper'.
Is there a way to have mypy ignore errors on this line? I was hoping that I could do something like this to have mypy skip that line:
from yaml import load, dump
    from yaml import CLoader as Loader, CDumper as Dumper  # nomypy
except ImportError:
    from yaml import Loader, Dumper
You can ignore type errors with # type: ignore as of version 0.2 (see issue #500, Ignore specific lines):
PEP 484 uses # type: ignore for ignoring type errors on particular lines ...
Also, using # type: ignore close to the top of a file [skips] checking that file altogether.

Source: mypy#500. See also the mypy documentation.
                @GregHilston ah, ouch. Unfortunately I don't know if this is possible (PEP 484 doesn't seem to list many other options), though it is possible to ignore an entire function (mypy#557).
– Salem
                Aug 30, 2019 at 21:51
                @GregHilston you could split the line using `\` or parenthesis and write the comment to the line where the mypy error occurs.
– steffen
                Dec 29, 2019 at 19:43
                To be more specific, MyPy supports specifying the error code/s to ignore with type: ignore[code, ...]. See mypy.readthedocs.io/en/stable/…. In this case, it would be # type: ignore[attr-defined].
– Gino Mempin
                Jan 2, 2021 at 11:00
Also # mypy: ignore-errors at the top of the file you want to ignore all errors works, if you are using shebang and coding lines should be like this:
#!/usr/bin/env python 
#-*- coding: utf-8 -*-
# mypy: ignore-errors
Gvanrossum comment
                Note this ignore all errors on the whole file, not just errors on a single line like what OP was asking about.
– bfontaine
                Feb 18, 2022 at 17:46
                That's why I write "all", sure it is not the accepted answer like the OP wanted, but just an complement to this thread. If you want to add to the answer write an edit or another answer :)
– Alan Garrido
                Feb 19, 2022 at 0:16
Of course, the answer of this question is add # type:ignore at the end of the line that want mypy to ignore it.
When I was google for how to ignore the files for django migrations,

this question was recomment to me several times.
So I post an answer about how to ignore Django migrations:
# mypy.ini
[mypy-*.migrations.*]
ignore_errors = True
And for mypy>=0.910, pyproject.toml is supported which can be set as follows:
[tool.mypy]
python_version = 3.8
ignore_missing_imports = true
[[tool.mypy.overrides]]
module = "*.migrations.*"
ignore_errors = true
                Note that this will ignore errors for the entire file and for all types of errors, not just for  the error on a specific line (which the OP was originally asking about).
– Gino Mempin
                Jan 2, 2021 at 10:58
        
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