# Mypy is interpreting missing symbols as \`Any\`?

**URL:** <https://discuss.python.org/t/mypy-is-interpreting-missing-symbols-as-any/81542>\
**Category:** Typing\
**Tags:** help, typing\
**Created:** [February 21, 2025, 4:58am UTC](https://discuss.python.org/t/mypy-is-interpreting-missing-symbols-as-any/81542 "2025-02-21T04:58:53Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![Andrej730](https://sea2.discourse-cdn.com/flex002/user_avatar/discuss.python.org/andrej730/32/19993_2.png) [@Andrej730](https://discuss.python.org/u/Andrej730)\
**Post date:** [February 21, 2025, 4:58am UTC](https://discuss.python.org/t/mypy-is-interpreting-missing-symbols-as-any/81542/1 "2025-02-21T04:58:53Z")

</div>

Python 3.11, mypy 1.15.0

Simple setup.  
test.py:

```python
from test_package import weird_symbol

def test(d: weird_symbol[str, list[int]]):
    print(d.items())
    reveal_type(d)

```

`test_package` located in `site-packages` that has 3 files: ` __init__.py`, `py.typed` (both just empty files) and ` __init__.pyi`:

```python
from collections import defaultdict as weird_symbol

__all__ = ['weird_symbol']

```

Running mypy check on this have this result:

```python
> py -3.11 -m mypy test.py
test.py:5: note: Revealed type is "collections.defaultdict[builtins.str, builtins.list[builtins.int]]"
Success: no issues found in 1 source file

```

But if we mess with a stub file a bit making it import unknown symbol

```python
from collections_ import defaultdict as weird_symbol

__all__ = ['weird_symbol']

```

There will be no errors, it will just interpret unknown symbol as `Any`. Is it normal? I expected it to fail at least in some way indicating that there’s a missing symbol.

```python
py -3.11 -m mypy test.py
test.py:5: note: Revealed type is "Any"
Success: no issues found in 1 source file

```

Why it’s important - noticed this because one of the files had something like `from typing import TypeIs` (which is only available in Python 3.12) which led to some false negatives because some symbols were just replaced with `Any` and had no real effect.

---

<div class="post-metadata">

**Author:** ![hauntsaninja](https://sea2.discourse-cdn.com/flex002/user_avatar/discuss.python.org/hauntsaninja/32/12451_2.png) [@hauntsaninja](https://discuss.python.org/u/hauntsaninja)\
**Post date:** [February 21, 2025, 5:19am UTC](https://discuss.python.org/t/mypy-is-interpreting-missing-symbols-as-any/81542/2 "2025-02-21T05:19:34Z")

</div>

Yes, mypy usually does not report errors in installed packages to users.

You could probably change this using some combination of the advanced and very-easy-to-incorrectly-use per-module options `follow_imports` + `follow_imports_for_stubs`.

For your use case when the stub is something mypy will check, this is what I get:

```python
λ cat y.pyi
from typing import TypeIs

λ python3.11 -m mypy y.pyi
y.pyi:1: error: Module "typing" has no attribute "TypeIs" [attr-defined]
y.pyi:1: note: Use `from typing_extensions import TypeIs` instead
y.pyi:1: note: See https://mypy.readthedocs.io/en/stable/runtime_troubles.html#using-new-additions-to-the-typing-module
Found 1 error in 1 file (checked 1 source file)

```

---

<div class="post-metadata">

**Author:** ![Andrej730](https://sea2.discourse-cdn.com/flex002/user_avatar/discuss.python.org/andrej730/32/19993_2.png) [@Andrej730](https://discuss.python.org/u/Andrej730)\
**Post date:** [February 21, 2025, 5:10pm UTC](https://discuss.python.org/t/mypy-is-interpreting-missing-symbols-as-any/81542/3 "2025-02-21T17:10:37Z")

</div>

> [@hauntsaninja](#):
>
> For your use case when the stub is something mypy will check, this is what I get:

Yeah, it does work perfectly for running mypy directly on some file or if importing local modules.

I’ve found the solution for my problem - the way to unsupress the errors from packages imported from `site-packages` is to set `no_silence_site_packages` flag, which is disabled by default ([The mypy configuration file - mypy 1.15.0 documentation](https://mypy.readthedocs.io/en/stable/config_file.html#confval-no_silence_site_packages)).