env.md

Python Virtual Environments

How to create and use virtual environments in Python.

📝 Cheatsheet: How to Create a Project with Separate venv

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📦 When to Use

• Each separate project should have its own virtual environment (venv).
• To keep project libraries isolated.
• To make projects portable and easy to maintain.

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🛠️ Steps for Every New Project

1. Go to your main repository folder (e.g., coding_school/):

   cd ~/projects/coding_school

2. Create a folder for the new project:

   mkdir project_name
   cd project_name

3. Create a virtual environment inside this folder:

   python3 -m venv venv

   🔹 Why venv twice?

   • First venv = Python module to create virtual environments.
   • Second venv = The folder name for your environment (you can name it anything, but venv is common).

4. Activate the virtual environment:

   source venv/bin/activate

5. Install necessary libraries:

   pip install requests
   pip install Pillow

6. Save installed libraries into requirements.txt:

   pip freeze > requirements.txt

7. Create your main code file:

   touch main.py

8. Check your .gitignore at repository root:
   Add this line:

   */venv/

   To make sure Git does not track your venv folders.

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📍 Example Project Structure

coding_school/
├── .gitignore
├── project1/
│   ├── venv/
│   ├── main.py
│   ├── requirements.txt
│   └── README.md
├── project2/
│   ├── venv/
│   ├── main.py
│   ├── requirements.txt
│   └── README.md

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🧠 Quick Reference Table

Action	Command
Create a new project	mkdir project_name
Create a new venv	python3 -m venv venv
Activate the venv	source venv/bin/activate
Install libraries	pip install ...
Save dependencies	pip freeze > requirements.txt
Protect venv in Git	Add */venv/ to .gitignore

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✨ SUMMARY

One project → One folder → One venv → One requirements.txt

Stay organized and professional!