package-management.md

Pyhon Language Overview

Package Management

Reference:

• https://docs.python.org/3/installing/index.html#installing-index
• https://packaging.python.org/tutorials/installing-packages

When you install Python, you also get Python's package manager, pip. Use pip to install and manage third-party Python packages.

List packages currently installed:

# For Homebrew-installed Python 3.x on Mac OS:
pip3 list

# All others:
pip list

Install a package (where my_package is the name of the package you want to install):

# For Homebrew-installed Python 3.x on Mac OS:
pip3 install my_package

# All others:
pip install my_package

Project-specific Package Management

You can specify and manage project-specific package dependencies by listing them in a file called requirements.txt in the project's root directory.

To specify a project's dependencies, first create a new requirements.txt file in your repository's root directory:

cd /path/to/your/project

# Mac Terminal:
touch requirements.txt

# Windows Command Prompt:
type nul > requirements.txt

Then revise the requirements.txt file. Write the name of each required Python package dependency on a new line, save the file, and exit. For example:

ipython
pytest
requests

NOTE: if you need to install a package from its Github source, use an entry like the following: git+https://github.com/eskerda/pybikes.git.

Finally, install package dependencies, as necessary:

# For Homebrew-installed Python 3.x on Mac OS:
pip3 install -r requirements.txt

# All others:
pip install -r requirements.txt

If you are experiencing installation or versioning errors when using Pip, you might consider using Pipenv instead, for project-specific package management.