use Python venv

use-python-venv.md

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+# Use Python venv
+
+Python venv is Python Virtual Environment. Why do we need to use Python venv ? Because we don't want to mess up with Python packages which are stored in different location: system directories, user directories, ...
+
+Assume you use Python 3 and Linux.
+
+---
+
+Python venv stores everything in a local directory.
+
+Inside a directory, run:
+
+```sh
+python -m venv venv
+```
+
+Now you can use venv with:
+
+```sh
+source ./venv/bin/activate
+```