requirements.txt & Dependency Management

# Generate requirements.txt
# pip freeze > requirements.txt

# Install from requirements.txt
# pip install -r requirements.txt

# Version specifiers:
# package==1.0    exact version
# package>=1.0    minimum version
# package~=1.0    compatible release (1.x)
# package>=1.0,<2.0  range

# Example requirements.txt
print("=== Project Dependencies ===")
deps = {
    "requests": "2.31.0",
    "beautifulsoup4": "4.12.2",
    "pytest": "7.4.3",
    "python-dotenv": "1.0.0",
    "click": "8.1.7",
}
for pkg, ver in deps.items():
    print(f"  {pkg}=={ver}")

# Development vs Production
print("\n--- dev-requirements.txt ---")
dev_deps = ["pytest==7.4.3", "black==23.12.0", "flake8==6.1.0", "mypy==1.7.0"]
for d in dev_deps:
    print(f"  {d}")

# Modern alternatives:
# - pyproject.toml (PEP 621)
# - poetry (dependency management + packaging)
# - pipenv (venv + pip combined)