[Fixed] attributeerror: Module h11 has no attribute event

This module covers the ‘attributeerror: module h11 has no attribute event’. But first, you should know what the h11 module is. Scroll down to know the reasons for the error.

About the h11 module and event attribute

The h11 module is a module that is commonly used along with libraries like Pycaret and httpcore. It has the ability to parse HTTP headers and messages. The Event attribute is representative of this module’s event. This is a class that holds necessary details like request header, response header, or data chunk.

Reasons of error

You can get the attributeerror: module h11 has no attribute event error due to the following reasons:

  • The h11 module is not updated.
  • You haven’t installed this module properly.
  • There can be dependency issues.

Primary Method of resolving the attributeerror: module h11 has no attribute event error

You should install the h11 module and upgrade it to get rid of the “attributeerror: module h11 has no attribute event” error. Also, the module’s dependencies include pycaret and httpcore libraries. Thus, you should downgrade these two libraries. The following code shows how you can proceed with these steps.

Check the location of the installed library and modify this command accordingly.

pip install h11
pip install --upgrade h11
pip install httpcore==0.15
pip install pycaret==1.0.2

Apart from this, you need to consider the documentation of this module once. This will make you aware of its usage and classes.

Also, you should check if spelling errors exist. It can be the capitalization of a word or any unwanted punctuation mark.

Solving ‘attributeerror: module h11 has no attribute event’ on GitHub

If you’re stuck with the “attributeerror: module h11 has no attribute event” error, you should first check in the terminal/command prompt whether the h11 module exists. For this, you can use the importlib module. The importlib.util.find_spec() present in this library will tell you if the h11 module actually exists or not. You don’t need to import any module for this.

import importlib.util

spec = importlib.util.find_spec("h11")

if spec is not None:
    print("h11 module is installed")
    print("h11 module is not installed")

After this, you need to follow the steps that have been covered above. This solution can work with GitHub codespace as well. It is suitable for other IDEs too.

Solving with stable diffusion

In order to resolve the ‘attributeerror: module h11 has no attribute event’ error, you should first move to the webui directory of stable diffusion on your system. After that, you should install the httpcore library in a virtual environment. –force-reinstall will reinstall this library with the 0.15 version even if it pre-exists.

cd stable-diffusion-webui
source venv/bin/activate
pip install --force-reinstall httpcore==0.15

Solving the ‘attributeerror: module h11 has no attribute event’ error in your conda environment

In order to fix the “attributeerror: module h11 has no attribute event”, you can check out the given code. First, you should consider uninstalling the httpcore and h11 packages. You can go ahead with this with the help of the uninstall option. Create a new environment and install these two packages in the new environment. Replace <env name> with the actual name of your virtual environment.

pip uninstall httpcore h11
conda install -n <env name> httpcore h11

Solving the ‘attributeerror: module h11 has no attribute event’ error on Ubuntu

In order to solve this error on Ubuntu, the primary method works. Other than that, you can follow the given steps, too.

  • See the system logs. Ubuntu logs like var/log/syslog and /var/log/dpkg.log might have details of the error.
  • Check online Ubuntu troubleshooting forums to see if the error is still unresolved.
  • The error may be deeply embedded in the system. In this case, you need to go for a reinstallation.
  • Check file permissions with the ls -l command. Sometimes, this is also the reason for your error.


Are there any alternatives to using the h11 module?

Yes, you may use httpcore and requests libraries to parse the HTTP data and operate on HTTP operations.


This article enhances your comprehension of the attributeerror: module h11 has no attribute event. It uncovers additional information pertaining to the solutions of the error.

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