How to Start a Python Project

These steps will help you set up and manage a Python environment on macOS, using Homebrew.

Watch how I used Cursor to learn about python environments:

TLDR

# Install Python3 with Homebrew
brew install python3

# Create a virtual environment
python3 -m venv my-venv

# Activate a virtual environment
source my-venv/bin/activate

# Install packages packages
pip install <package-name>

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

# Deactivate an active virtual environment
deactivate

Install Python3

If not installed, use your system package manager to install Python3.

Instructions here use Homebrew for macOS.

brew install python3

Create a Virtual Environment with `venv`

python3 -m venv my-venv

Use any directory name you like.

Activate a Virtual Environment with `source`

source my-venv/bin/activate

Install Packages with `pip`

pip install <package-name>

Example: pip install awscli

Generate a `requirements.txt` file with `pip freeze`

pip freeze > requirements.txt

The resulting file will look like this:

awscli==1.34.10
botocore==1.35.10
colorama==0.4.6
docutils==0.16
jmespath==1.0.1
pyasn1==0.6.0
python-dateutil==2.9.0.post0
PyYAML==6.0.2
rsa==4.7.2
s3transfer==0.10.2
six==1.16.0
urllib3==2.2.2

Deactivate the Virtual Environment

deactivate

Some prefer `virtualenv` over `venv`

While Python3 comes with venv by default, some use virtualenv for “additional features” — though I can’t speak directly to the differences.

How to Start a Python Project

TLDR

Install Python3

Create a Virtual Environment with venv

Activate a Virtual Environment with source

Install Packages with pip

Generate a requirements.txt file with pip freeze