Using IntellijIdea within an existing virtualenv

For PyCharm 2018

As per documentation from Pycharm:

In the Project Interpreter page, click and select Add. In the left-hand pane of the Add Python Interpreter dialog box, select Virtualenv Environment. The following actions depend on whether the virtual environment existed before. If Existing environment is selected: Specify the required interpreter: use the drop-down list, or click Select an interpreter and find one in your file system. Select the check-box Make available to all projects, if needed. Click OK to complete the task.

For Pycharm 2016 and later

To add an existing virtual environment to the list of available interpreters

In the Project Interpreter page, click . In the drop-down list, choose Add local.

https://i.stack.imgur.com/I226A.png

In the Select Python Interpreter dialog box that opens, choose the desired Python executable, located inside the virtual environment folder, and click OK.

Go to this link for more information.

For Older versions:

https://i.stack.imgur.com/aFAgO.jpg

https://i.stack.imgur.com/F9hjd.jpg

https://i.stack.imgur.com/gblfE.png

https://i.stack.imgur.com/6nSlE.jpg

https://i.stack.imgur.com/0nhSq.jpg

Now need to run the project.

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The above answer is based on older version of IntelliJ. For new, look here: https://www.jetbrains.com/help/pycharm/2016.1/adding-existing-virtual-environment.html

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