Can access attribute "__args__" for local class "TypeAliasType", but Cannot access attribute "__args__" for imported class "TypeAliasType"
question
Type: <b>Bug</b>
The local version of the code does not produce diagnostics, but the imported version does.
```python
from __future__ import annotations
from soundfile import dtype_str
from typing import Literal, TypeAlias
dtype_str_local: TypeAlias = Literal['float64', 'float32', 'int32', 'int16']
qq = dtype_str_local.__args__
ww = dtype_str.__args__
```
<details><summary>Cannot access attribute "__args__" for class "TypeAliasType"</summary>
<p>
```json
[{
"resource": "/C:/apps/hunterHearsPy/ee.py",
"owner": "Pylance",
"code": {
"value": "reportAttributeAccessIssue",
"target": {
"$mid": 1,
"path": "/microsoft/pylance-release/blob/main/docs/diagnostics/reportAttributeAccessIssue.md",
"scheme": "https",
"authority": "github.com"
}
},
"severity": 8,
"message": "Cannot access attribute \"__args__\" for class \"TypeAliasType\"\n Attribute \"__args__\" is unknown",
"source": "Pylance",
"startLineNumber": 9,
"startColumn": 16,
"endLineNumber": 9,
"endColumn": 24,
"modelVersionId": 34,
"origin": "extHost1"
}]
```
</p>
</details>
Which I assume necessarily leads to
<details><summary>Type of "__args__" is unknown</summary>
<p>
```json
[{
"resource": "/C:/apps/hunterHearsPy/ee.py",
"owner": "Pylance",
"code": {
"value": "reportUnknownMemberType",
"target": {
"$mid": 1,
"path": "/microsoft/pylance-release/blob/main/docs/diagnostics/reportUnknownMemberType.md",
"scheme": "https",
"authority": "github.com"
}
},
"severity": 8,
"message": "Type of \"__args__\" is unknown",
"source": "Pylance",
"startLineNumber": 9,
"startColumn": 6,
"endLineNumber": 9,
"endColumn": 24,
"modelVersionId": 34,
"origin": "extHost1"
}]
```
</p>
</details>
The Python interpreter can see the `__args__` attribute.
<details><summary>Details</summary>
<p>
```pycon
(hunterhearspy) C:\apps\hunterHearsPy>ver
Microsoft Windows [Version 10.0.26200.8655]
(hunterhearspy) C:\apps\hunterHearsPy>py
Python 3.14.5 (tags/v3.14.5:5607950, May 10 2026, 10:43:50) [MSC v.1944 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
Ctrl click to launch VS Code Native REPL
>>> from soundfile import dtype_str
>>> dtype_str.__dir__()
['__origin__', '__str__', '__or__', '__init_subclass__', '_inst', '__args__', '__ror__', 'copy_with', '__mro_entries__', '__getitem__', '__subclasshook__', '_getitem', '__static_attributes__', '__doc__', '__setattr__', '__le__', '__gt__', '_make_substitution', '__instancecheck__', '__ge__', '_name', '__getattribute__', '__format__', '__class__', '__dir__', '_determine_new_args', '__reduce_ex__', '__weakref__', '__new__', '__ne__', '__repr__', '__subclasscheck__', '__getstate__', '__init__', '__eq__', '__firstlineno__', '__delattr__', '__sizeof__', '__slots__', '__call__', '__getattr__', '__hash__', '__parameters__', '__module__', '__lt__', '__iter__', '__dict__', '__reduce__']
>>> dtype_str.__args__
('float64', 'float32', 'int32', 'int16')
>>> type(dtype_str.__args__)
<class 'tuple'>
```
</p>
</details>
---
Extension version: 2026.2.104
VS Code version: Code - Insiders 1.125.0-insider (d7ce0ce923f97583f7e03f9c17a149b1601090a3, 2026-06-11T13:27:59+10:00)
OS version: Windows_NT x64 10.0.26200
Modes:
<details>
<summary>System Info</summary>
|Item|Value|
|---|---|
|CPUs|AMD Ryzen 7 5700U with Radeon Graphics (16 x 1797)|
|GPU Status|2d_canvas: enabled<br>GPU0: VENDOR= 0x1002, DEVICE=0x164c [AMD Radeon(TM) Graphics], DRIVER_VENDOR=AMD, DRIVER_VERSION=31.0.21925.1001 *ACTIVE*<br>GPU1: VENDOR= 0x1414, DEVICE=0x008c [Microsoft Basic Render Driver], DRIVER_VERSION=10.0.26100.8521<br>Machine model name: <br>Machine model version: <br>direct_rendering_display_compositor: disabled_off_ok<br>gpu_compositing: enabled<br>multiple_raster_threads: enabled_on<br>opengl: enabled_on<br>rasterization: enabled<br>raw_draw: disabled_off_ok<br>skia_graphite: disabled_off<br>trees_in_viz: disabled_off<br>video_decode: enabled<br>video_encode: enabled<br>webgl: enabled<br>webgpu: enabled<br>webnn: disabled_off|
|Load (avg)|undefined|
|Memory (System)|12.90GB (3.10GB free)|
|Process Argv||
|Screen Reader|no|
|VM|0%|
</details>
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关闭于 2026-06-11 2 条评论