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exercises/Exercise 5a Virtual Environments.md

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+## Exercise 5a: Virtual Environments
+
+#### Goal
+
+Create a virtual environment + install a package + see that that package was installed only in environment
+
+#### Tasks
+
+We will use `venv` as our environment manager - while commands might differ, the principles apply to all other package managers as well.
+
+1. Check which Python you are currently using, and which packages are installed. Also check which folders are in the folder you are installing the environment into.
+3. Create and activate a new environment.
+4. Check again which Python you are using and which packages are installed - are they different?
+5. Install a specific version of a package using pip e.g. pandas=1.5.3
+6. See that dependencies are also installed (more packages than only pandas appear)
+7. Deactivate and delete the environment
+8. Check the packages that are installed when no environment is active again (as step 1). Have they changed?
+
+
+#### Commands in case you get stuck (not in correct order):
+
+```bash
+% investigate Python and packages
+> which python
+> pip freeze
+> pip install <package-name>
+> pip install <package-name>==0.0.1
+
+% create an environment option 1 (create folder called venv_folder for files related to virtual environment, feel free to change the name)
+> cd <path-to-project_folder>
+> mkdir venv_folder
+> python3 -m venv venv_folder
+> source venv_folder/bin/activate
+
+% create an environment option 2
+> python3 -m venv <path-to-folder-for-venv>
+> source <path-to-folder-for-venv>/bin/activate
+
+% deactivate and delete a venv environment
+> deactivate
+> rm -rf venv_folder
+```