If you have both Python 2 and Python 3 installed (common on Linux/macOS), use:
Additionally, you’ll see:
New libraries often require newer Python versions.
Setting up automated version switching takes less than a minute. Follow these steps using pyenv as the primary example. 1. Install the Desired Python Version
: GitHub Actions can read this file using the python-version-file property in the setup-python action. Python versions | uv - Astral Docs .python version
Python is a high-level, interpreted programming language that has undergone significant changes and improvements over the years. The language has evolved through various versions, each introducing new features, enhancements, and bug fixes. In this write-up, we'll explore the different Python versions, their notable features, and the significance of each.
The ecosystem is trending toward that combine version management, virtual environments, and dependency resolution into a single binary. Projects like uv (Rust), rye (Python itself), and pdm are leading this shift.
To help tailor this setup to your exact workflow, please consider the following next steps:
FROM python:3.13-slim WORKDIR /app COPY requirements.txt . RUN pip install -r requirements.txt COPY . . CMD ["python", "app.py"] If you have both Python 2 and Python
The quickest way to check your installed version is through your system's terminal. python --version Specific to Python 3: python3 --version Windows Launcher: py --version
:
The humble .python-version file is a cornerstone of reproducible Python development. By combining it with pyenv , you gain precise control over which interpreter runs your code, no matter how many projects you juggle. Whether you are a solo developer or part of a large team, adopting this practice will eliminate “but it works on my machine” problems related to Python versions.
FROM python:$(cat .python-version)-slim WORKDIR /app COPY . . RUN pip install -r requirements.txt CMD ["python", "app.py"] The language has evolved through various versions, each
If you are containerising an application, you should rely on .python-version inside the container. Instead, use a base image like python:3.11-slim in your Dockerfile . However, you can use the .python-version file to generate the Dockerfile automatically:
Master your Python versions, and you master your environment. Happy coding!
: Fast Python packaging tooling by Astral that integrates seamlessly with existing version files. How to Create and Use .python-version
In an interactive session, you can also type: