Virtual Environments (venv)

# Why virtual environments?
# Project A needs requests==2.28
# Project B needs requests==2.31
# Without venv, they conflict!

# Creating a virtual environment:
# python -m venv myenv        # create
# myenv\Scripts\activate      # activate (Windows)
# source myenv/bin/activate   # activate (macOS/Linux)
# deactivate                  # deactivate

# Workflow:
# 1. Create project directory
# 2. Create venv: python -m venv venv
# 3. Activate: venv\Scripts\activate
# 4. Install packages: pip install requests
# 5. Save deps: pip freeze > requirements.txt
# 6. Deactivate when done: deactivate

# requirements.txt example:
requirements = """requests==2.31.0
beautifulsoup4==4.12.2
python-dotenv==1.0.0
pytest==7.4.3"""

print("=== requirements.txt ===")
print(requirements)

# Recreate environment:
# pip install -r requirements.txt

# .gitignore — always ignore venv!
gitignore = """# Virtual environment
venv/
.env
__pycache__/
*.pyc"""

print("\n=== .gitignore ===")
print(gitignore)