ModuleNotFoundError: No module named 'matplotlib'

This error message means that the Python module 'matplotlib' cannot be found. This module is a third-party library for creating visualizations and graphs in Python.

To fix this error, you need to install the 'matplotlib' module. You can do this by running the following command in your terminal:

pip install matplotlib

This will install the 'matplotlib' module and make it available for use in your Python code.