How to fix the modulenotfounderror no module named langchain in VSCode, and Jupyter?

Understand the no module named langchain in Python

The fundamental issue is that your Python program cannot locate the langchain module. Most probably, the module is not installed in the environment you’re using or is installed in a different Python environment that the IDE is not configured to use.

Read on to learn how to troubleshoot and fix the issue in each IDE.

Fixing the langchain error in Visual Studio Code

  • Ensure that you’ve installed the langchain module by running the following command in the terminal (if using macOS or Linux) or using the command line in Windows:
pip install langchain 
  • If you’re using a virtual environment, make sure the environment is currently activated.
  • Check that VSCode is using the correct interpreter by looking at the bottom-left corner. If not, select the correct interpreter where langchain is installed.
  • If the issue persists, try reloading the window or restarting VSCode.

Fixing the error in Jupyter

  • Activate your environment and open Jupyter Notebook or Lab.
  • Install the langchain package by typing the following command on your notebook cell:
!pip install langchain
  • If that doesn’t work, make sure you have the correct kernel selected.
  • You can change the kernel by clicking on Kernel and then select Change kernel. Then select, the one associated with the environment where langchain is installed.

Fixing the error in PyCharm

  • In Pycharm, go to FIle and Then select Settings.
  • Then hit Project, and select your project name.
  • Then Select Project Interpreter,
  • Look for langchain in the list of selected packages.
  • If it’s not there, click the ‘+’ button to add it.
  • If langchain is installed in a virtual environment, you need to point PyCharm to that specific environment.