15. Working with pip
1. Introduction
pip is Python’s default package manager.
It allows you to install, update, and remove external libraries (packages) that extend Python’s functionality.
Most Python projects use pip to manage dependencies.
2. Checking if pip is Installed
Open a terminal or Command Prompt and run:
pip --version
or
pip3 --version
You should see something like:
pip 23.2.1 from /usr/local/lib/python3.12/site-packages/pip (python 3.12)
If you get an error, pip may not be installed.
3. Installing pip (if missing)
- On Windows, reinstall Python with the pip option checked.
- On Linux/macOS, install with:
sudo apt install python3-pip # Ubuntu/Debian
sudo dnf install python3-pip # Fedora
brew install pipx && pipx ensurepath # macOS with Homebrew
4. Installing a Package
To install a package:
pip install requests
This installs the requests library for making HTTP requests.
5. Using Installed Packages
After installation, you can import the package in Python:
import requests
response = requests.get("https://example.com")
print(response.status_code)
6. Listing Installed Packages
Check what’s installed:
pip list
Sample output:
numpy 1.26.0
pandas 2.1.1
requests 2.31.0
7. Upgrading Packages
Update a package to the latest version:
pip install --upgrade requests
Upgrade pip itself:
pip install --upgrade pip
8. Uninstalling Packages
Remove a package:
pip uninstall requests
9. Requirements Files
For larger projects, dependencies are stored in a file called requirements.txt.
- Create one:
pip freeze > requirements.txt
- Install all packages from it:
pip install -r requirements.txt
10. Troubleshooting
- Permission denied (Linux/macOS) → Use
pip install --user <package>. - pip installs wrong version → Make sure you use
pip3with Python 3. - PATH issues → Add the Python
Scripts/folder to PATH.
11. Next Steps
✅ You now know how to install and manage packages with pip.
In the next chapter, we’ll explore virtual environments, which let you manage project-specific dependencies.