How to Install `aiosignal` in Python

v1.4.0 Async & Networking Python >=3.9 Apache 2.0

aiosignal: a list of registered asynchronous callbacks

Install pip install aiosignal

What is aiosignal?

aiosignal: a list of registered asynchronous callbacks

A project to manage callbacks in projects.

`` is a list of registered asynchronous callbacks.

The signal's life-cycle has two stages: after creation its content could be filled by using standard list operations: `` etc.

Documentation → PyPI page →

Quick Start

Minimal example to get started with aiosignal:

import aiosignal

print(aiosignal.__version__)

Installation

pip (standard)

pip install aiosignal

Virtual environment (recommended)

python -m venv venv
source venv/bin/activate   # Windows: venv\Scripts\activate
pip install aiosignal

pip3

pip3 install aiosignal

conda

conda install -c conda-forge aiosignal

Poetry

poetry add aiosignal

Dependencies

Installing aiosignal will also install these packages:

frozenlist typing-extensions

Verify the Installation

After installing, confirm the package is available:

python -c "import aiosignal; print(aiosignal.__version__)"

If this prints a version number, installation succeeded. If you see a ModuleNotFoundError, see the errors section below.

Installation Errors

Common errors when installing aiosignal with pip.

ModuleNotFoundError: No module named 'aiosignal'

Cause: The package is not installed in the current Python environment.

Fix: Run pip install aiosignal. If using a virtual environment, ensure it is activated first.

ModuleNotFoundError: No module named 'aiosignal' (installed but still failing)

Cause: pip installed the package into a different Python than the one running your script.

Fix: Use python -m pip install aiosignal to install into the interpreter you are running.

ImportError: cannot import name 'X' from 'aiosignal'

Cause: The function or class does not exist in the installed version.

Fix: Check the version with pip show aiosignal and upgrade with pip install --upgrade aiosignal.

pip: command not found

Cause: pip is not in PATH or Python was not added to PATH during installation.

Fix: Try python -m pip install aiosignal. On macOS/Linux try pip3.

PermissionError: [Errno 13] Permission denied

Cause: No write access to the system Python package directory.

Fix: Use a virtual environment, or add --user: pip install --user aiosignal

SSL: CERTIFICATE_VERIFY_FAILED

Cause: pip cannot verify PyPI's SSL certificate — common behind corporate proxies.

Fix: Try: pip install --trusted-host pypi.org --trusted-host files.pythonhosted.org aiosignal

RuntimeError: This event loop is already running

Cause: Calling <code>asyncio.run()</code> inside Jupyter or another already-running event loop.

Fix: In Jupyter, use await directly. Or install nest_asyncio and call nest_asyncio.apply().

Recent Releases

Version	Released
`1.4.0` latest	2025-07-03
`1.3.2`	2024-12-13
`1.3.1`	2022-11-08
`1.2.0`	2021-10-16
`1.2.0a0`	2021-10-16

Full release history on PyPI →

Manage aiosignal

Upgrade to latest version

pip install --upgrade aiosignal

Install a specific version

pip install aiosignal==1.4.0

Uninstall

pip uninstall aiosignal

Check what is installed

pip show aiosignal

Last updated: 2026-04-11 • Data from PyPI

How to Install aiosignal in Python