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Questions tagged [pylance]

Pylance is an extension for Visual Studio Code that provides a language server for Python. When applying this tag to your question, consider also tagging it with [visual-studio-code] and/or [python].

Pylance is a language server to support the core Python extension for Visual Studio Code. Its aim is to help developers write Python code better and faster by providing auto-imports, semantic highlighting, built-in reporting of warnings and errors, strict type-checking, and method signatures with type information when displaying the popup Intellisense documentation.

It was first introduced in a post on Microsoft's Python development blog: Announcing Pylance: Fast, feature-rich language support for Python in Visual Studio Code:

To deliver an improved user experience, we’ve created Pylance as a brand-new language server based on Microsoft’s Pyright static type checking tool. Pylance leverages type stubs (.pyi files) and lazy type inferencing to provide a highly-performant development experience. Pylance supercharges your Python IntelliSense experience with rich type information, helping you write better code, faster. The Pylance extension is also shipped with a collection of type stubs for popular modules to provide fast and accurate auto-completions and type checking.

It was made available starting VS Code 1.49 (2020.8.0 (12 August 2020) release).

  1. Expose Pylance setting in python.languageServer. If Pylance extension is not installed, prompt user to install it. (#13122)

Installation is straightforward:

  1. Install the Pylance extension
  2. Configure your settings.json file 
    "python.languageServer": "Pylance",
  3. Open a .py file and the extension should activate

For more information:

465 questions
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Python @property method violating Protocol variable type annotation

I have an interface class Moveable(Protocol): position: Tuple[int, int] I implement the interface with a class that happens to use a getter to imitate the attribute position: Tuple[int, int] class Player: _x: int _y: int @property …
Michael Moreno
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How to annotate types for columns in sqlalchemy model

How do I annotate the columns in my model? The following seems to mostly work: class MyModel(Base): __tablename__: str = 'mytable' id: str = db.Column(db.String(32), primary_key=True) test: int = db.Column(db.Integer, index=True) …
Jaime Salazar
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Why does pylance point out a type issue when using ABCMeta.register?

Example code using register to add C as a virtual subclass of A: from abc import ABC, abstractmethod class A(ABC): @abstractmethod def f(self) -> int: ... class B(A): # normal subclass def f(self) -> int: return…
myke
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vscode doesn't show code action (import python function from python.analysis.extraPaths)

I try to import a function (print_pretty_table) which is located in pretty_table_yaml_json so I add the following code to setting.json, it doesn't give 'show code action' which could help me do "from pretty_table_yaml_json.api import…
user1334609
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vscode python lint problem at the first column of first line

I have python modules that I run in VSCode for development. And everything works fine until today VSCode suddenly said that one of the module had some binding problem and made the file name tab red. VSCode the problem occurs in the first character…
Farn Wang
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Python type-checker can't tell we're dealing with subclasses

Say I have some code like this: from typing import Any class Parent: def __init__(self, name: Any): self.name = name class Child(Parent): def __init__(self, name: Any): super().__init__(name) def print_name(self) ->…
Nick Reid
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Pylance: wont find stubs for native library with submodules

Edit: I also posted this question as an issue on pylance-release github repo, which might be better suited to find an answer. I'm having issues with Visual Studio Code python language server, which cannot find the stubs for a python binding library…
Pascal T.
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Precise type annotating array (numpy.ndarray) of matplotlib Axes from plt.subplots()

I wanted to have no errors while using VSCode Pylance type checker. How to type the axs correctly in the following code: import matplotlib.pyplot as plt fig, axs = plt.subplots(2, 2) In the image below, you can see that Pylance on VSCode is…
Onyr
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How to solve pylance server crashing in VS Code?

Beginner here in coding/programming. I'm doing the MOOC from Helsinki University. Using VS Code and the TMC plugin is a must because I admit my solutions through it. Pylance server keeps on crashing every few days. I can't find a solution for it.…
Karim
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VSC doesn't show import suggestion from django

I wonder why my Visual studio code doesn't show me import suggestion from Django framework but show suggestions from other packages? I have installed Pylance and already add this line in settings.json: "python.languageServer": "Default" Anyone…
Pytolong
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In Python, how do I make a decorator class with a method that has the same signature as the function it wraps?

Here's an example of what I'm trying to do: from typing import Callable, Generic, ParamSpec, TypeVar t_Params = ParamSpec("t_Params") t_Ret = TypeVar("t_Ret") class Wraps(Generic[t_Params, t_Ret]): _func: Callable[t_Params, t_Ret] def…
lapraswastaken
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No auto-completion in VS Code with Python extension (using Pylance)

I'm getting started with Python in VS Code. I've got the Python extension installed with IntelliSense from Pylance. Auto-completion has worked so far with some fairly simple pieces of code using built-in functions and methods, but now I'm playing…
luukburger
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How do I get Pylance's type checking to work with this Pydantic example?

I'm discovering Pydantic and I see this in an example (https://pydantic-docs.helpmanual.io/usage/models/#recursive-models): from pydantic import BaseModel class Foo(BaseModel): count: int size: float = None I'm using VS Code and Pylance,…
lapraswastaken
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Vscode how to disable type annotation in pylance

I recently switched to vscode for python but I'm having a bit of trouble with overzealous completions in pylance. Specially with function overrides, pylance seems to just automatically infer the types and inject annotations everywhere. I'd like to…
kale hops
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Pylance none-checking with a function

I have a class that requires a sequence of actions to be taken: class SomeModel: def __init__(self): pass def predict(self, X): return None class Model: def __init__(self): self.inner_model = None def…
Robert Jeffrey
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