Modulenotfounderror: no module named ‘fcntl’ [SOLVED]

This article will show you the solution for the error modulenotfounderror: no module named ‘fcntl’ in Python. This error is commonly encountered by Python programmers when the ‘fcntl’ module is not installed in their system or Python environment.

What is Python?

Python is one of the most popular programming languages. It is used for developing a wide range of applications. It is a high-level programming language that is usually used by developers nowadays due to its flexibility.

Returning to our issue, we must take a few actions to fix this error. So, without further ado, let’s move on to our “how to fix this error” tutorial.

How to solve “no module named ‘fcntl’” in Python

Unfortunately, the fcntl package is not available on Windows and is only available on Linux. However, you can use the alternative package, which you can install using pip.

Install the waitress package

The waitress package on Windows is a replacement for various Linux fcntl usages. Install this by entering the following command on your cmd or command prompt.

pip install waitress

The command pip install waitress will download and install the latest version of the waitress package on your system.

See also: Modulenotfounderror: no module named ‘flask.ext’ [SOLVED]

Commands you might need

  • pip list

    This command will display all the packages installed on your system, including their versions.

    If you’re using Jupyter Notebook, use the !pip list command instead of pip list. However, if you’re using Anaconda, use the command conda list.
  • python -m

    Include this command in your pip install waitress command if you get an error message stating that “pip” cannot be found. (example: python -m pip install waitress)

    However, if you’re using Python 3, use the command python3 -m pip install waitress instead of python -m pip install waitress.
  • pip install --upgrade pip

    Use this command to upgrade the pip package manager to its newest version. If your pip is already in the latest version, this will come out: “Requirement already satisfied.”
  • python --version

    Use this command if you want to check what version of Python you have.
  • pip show waitress

    Use this command to display information about your waitress package, including its location.

    If you’re using Jupyter Notebook, use the command !pip show waitress instead of pip show waitress.
  • pip install --upgrade waitress

    Use this command to upgrade your waitress package to its latest version. If it is already the latest version, this will come out: “Requirement already satisfied.”

    If you’re using Jupyter Notebook, use the command !pip install --upgrade waitress instead of pip install --upgrade waitress.


In conclusion, the error modulenotfounderror: no module named ‘fcntl’ can be solved by installing its alternative package in your Python environment.

By following the guide above, there’s no doubt that you’ll be able to resolve this error quickly.

We hope you’ve learned a lot from this. If you have any questions or suggestions, please leave a comment below, and for more Python tutorials, visit our website.

Thank you for reading!

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