Python Version Manager (pyvm)

A cross-platform CLI tool to check and install the latest Python version side-by-side with your existing Python installation.

CRITICAL UPDATE (v1.2.1)

If you are using v1.2.0 or earlier: Please update immediately.

Previous versions contained system-breaking code that could freeze Linux systems. v1.2.1 is completely safe and only installs Python without modifying system defaults.

# Update to the safe version
cd pyvm-updater
git pull
pip install --user -e .

See docs/CRITICAL_SECURITY_FIX_v1.2.1.md for details and recovery instructions.

Documentation: Installation Guide | Quick Start | Quick Reference

Quick Start

# Install the package
pip install --user pyvm-updater

# Use it
pyvm check      # Check your Python version
pyvm update     # Update to latest Python

Features

• Check your current Python version against the latest stable release
• Install the latest Python side-by-side with your existing version
• Cross-platform support (Windows, Linux, macOS)
• Detailed system information display
• Simple and intuitive CLI interface
• Safe: Never modifies your system Python defaults
• Multiple Python versions coexist peacefully
• Clear instructions on how to use the new version

Installation

From GitHub (For New Users)

# Clone the repository
git clone https://github.com/shreyasmene06/pyvm-updater.git
cd pyvm-updater

# Install
pip install --user .

Method 2: Install via pip (Published on PyPI)

pip install --user pyvm-updater

Note for Linux users: On newer systems (Ubuntu 23.04+, Debian 12+), use --user flag or see troubleshooting if you get "externally-managed-environment" error.

Method 3: Install via pipx (Recommended for CLI tools)

# Install pipx if you don't have it
sudo apt install pipx   # Ubuntu/Debian
# or: brew install pipx  # macOS

# Install pyvm-updater
pipx install pyvm-updater

# If pyvm command not found, add to PATH:
pipx ensurepath

# Then restart your terminal or run:
source ~/.bashrc   # or source ~/.zshrc

**Why pip with pip pip install --user .

Verify installation

pyvm --version pyvm check

All dependencies are automatically installed.

### Vthe `--user` flag or see [troubleshooting](#troubleshooting) if you encounter an "externally-managed-environment" error.

### Vb.com/shreyasmene06/pyvm-updater.git
cd pyvm-updater

# Optional: Check system requirements first
python3 check_reqencounter permission errors, use `pip install --user .` instead of `pip install .`

This will automatically install all required dependencies:

* requests
* beautifulsoup4
* packaging
* click

The `pyvm` command will be available globally after installation.

##ck
dependency conflicts.

### Fr are using Anaconda or Miniconda, the `pyvm update` command will install the latest Python to your system, but your Anaconda environment will continue using its own Python version. This is expected behavior.

**How to check:**
```bash
# Your Anaconda Python (unchanged)
python --version

# The newly installed system Python
python3.14 --version

To use the updated Python:

1. Use it directly: python3.14 your_script.py
2. Create a new environment: python3.14 -m venv myenv
3. Continue using Anaconda (recommended for data science work)

Why does this happen?

Anaconda manages its own Python installation separately from system Python. This prevents conflicts between your Anaconda packages and system packages.

For detailed installation instructions, see INSTALL.md

---

For detailed installation instructions, see INSTALL.md

📖 Usage

Check Python version

Simply run the tool to check your Python version:

pyvm
# or
pyvm check

Output example:

Checking Python version... (Current: 3.12.3)

========================================
WARNING: A new version (3.14.0) is available!

r version:   3.12.3
Latest version: 3.14.0
========================================
⚠ A new version (3.14.0) is available!

💡 Tip: Run 'pyvm update' to upgrade Python

Update Python

Update to the latest version:

pyvm update

For automatic installation without confirmation:

pyvm update --auto

IMPORTANT: This command installs Python side-by-side. Your system Python remains unchanged.

After Installing - How to Use the New Python

Once installation completes, the new Python is available side-by-side with your existing version:

Linux/macOS:

# Your old Python (unchanged)
python3 --version          # Shows: Python 3.10.x (or whatever you had)

# Your new Python (side-by-side)
python3.12 --version       # Shows: Python 3.12.x

# Use the new Python for a script
python3.12 your_script.py

# Create a virtual environment with the new Python
python3.12 -m venv myproject
source myproject/bin/activate
python --version           # Now shows 3.12.x in this venv

Windows:

# List all Python versions
py --list

# Use specific version
py -3.12 your_script.py

# Create virtual environment
py -3.12 -m venv myproject
myproject\Scripts\activate

Why doesn't python3 automatically use the new version?

This is intentional and safe! Your system tools (package managers, system utilities) depend on the Python version they were built with. Changing the default could break them. The tool gives you the new Python to use when YOU choose, without risking your system.

Show system information

pyvm info

Output example:

==================================================
           System Information
==================================================
Operating System: Linux
Architecture:     amd64
Python Version:   3.12.3
Python Path:      /usr/bin/python3
Platform:         Linux-5.15.0-generic-x86_64

Admin/Sudo:       No
==================================================

Show tool version

##--version

---
multiple Python versions side-by-side. Here i
## 🔄 Using Your New Python Version

After installation, you have **multiple Python versions** side-by-side. Here's how to use them effectively:

### Check Your Setup

```bash
# Your system Python (unchanged)
python3 --version          # Shows: Python 3.10.x

# Your new Python (side-by-side)
python3.12 --version       # Shows: Python 3.12.x

# See all installed versions
ls /usr/bin/python* | grep -E 'python[0-9]'

Best Practice: Use Virtual Environments (Recommended)

This is the safest and most flexible approach:

# Create project with new Python
python3.12 -m venv myproject
source myproject/bin/activate

# Now you're using the new Python in this project
python --version           # Shows: Python 3.12.x
pip install -r requirements.txt

# Deactivate when done
deactivate

* Isolated dependencies per project
* No system modifications
* Easy to switch between Python versions
* Isolated dependencies per project
- ✅ No system modifications
- ✅ Easy to switch between Python versions
- ✅ No risk of breaking system tools

### Alternative: Direct Invocation

Always specify which version you want:

```bash
# Run scripts with new Python
python3.12 your_script.py

# Install packages for new Python
python3.12 -m pip install requests

Option for Advanced Users: Change System Default

⚠️ Warning: Only do this if you understand the risks!

Warning: Only do this if you understand the risks.

Changing your system's default Python can break system tools. If you still want to proceed

Manually configure (at your own risk)

sudo update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.12 1 sudo update-alternatives --config python3

**We do NOT recommend this approach.** Virtual environments are much safer.

We do not recommend this approach. Virtual environments are much safer as they do no

Windows Python Launcher (`py`) handles multiple versions automatically:

```bash
# Use specific version
py -3.14 your_script.py

# List all versions
py --list

# Set default in py.ini (optional)
# Create/edit: C:\Windows\py.ini
# Add: [defaults]
#      python=3.14

or edit: C:\Windows\py.ini

Add: [defaults]

python=3.14

- Downloads the official Python installer (.exe)
- Runs the installer interactively
- **Recommendation**: Check "Add Python to PATH" during installation

### Linux
- Uses system package managers (apt, yum, dnf)

* Downloads the official Python installer (.exe)
* Runs the installer interactively
* **Recommendation**: Check "Add Python to PATH" during installation

### Linux

* Uses system package managers (apt, yum, dnf)
* May require `sudo` privileges
* For Ubuntu/Debian: Uses deadsnakes PPA for latest versions
* **Alternative**: Install pyenv for easier version management

### macOS

* Uses Homebrew if available
* Falls back to official installer download link
* Run `brew install python@3.x` for Homebrew installation

## Requirements

* Python 3.7 or higher
* Internet connection
* Admin/sudo privileges (for updates on some systems)

## Dependencies

* `requests` – HTTP library
* `beautifulsoup4` – HTML parsing
* `packaging` – Version comparison
* `click` –Check Python version (default) |
| `pyvm check` | Check Python version |
| `pyvm update` | Update Python to latest version |
| `pyvm update --auto` | Update without confirmation |
| `pyvm update --set-default` | Update and set as system default (Linux) |
| `pyvm update --auto --set-default` | Fully automated update and setup (Linux) |
| `pyvm set-default` | List available Python versions (Linux) |
| `pyvm set-default 3.12` | Set Python 3.12 as system default (Linux) |
| `pyvm info` | Show system information |
| `pyvm --version` | Show tool version |
| `pyvm --help` | Show help message |

## Exit Codes

- `0` - Success or up-to-date
- `1` - Update available or error occurred
- `130` - Operation cancelled by user (Ctrl+C)
* `0` – Success or up-to-date
* `1` – Update available or error occurred
* `130` – Operation cancelled by user (Ctrl+C)

##
**Error message:**

error: externally-managed-environment × This environment is externally managed

This is a security feature on newer Linux systems (Ubuntu 23.04+, Debian 12+) that prevents breaking system Python packages.

**Solutions:**

**Option 1: Use `--user` flag (Recommended)**
```bash
pip install --user pyvm-updater

Option 2: Use pipx (Best for CLI tools)

# Install pipx first
sudo apt install pipx

# Install pyvm-updater with pipx
pipx install pyvm-updater

Option 3: Use a virtual environment

python3 -m venv myenv
source myenv/bin/activate
pip install pyvm-updater

Option 4: Override (NOT recommended)

pip install --break-system-packages pyvm-updater  # ⚠️ Not recommended

"pyvm: command not found"

The installation directory is not in your PATH.

If you installed with pip install --user:

# Add to your ~/.bashrc or ~/.zshrc
export PATH="$HOME/.local/bin:$PATH"

# Then reload your shell
source ~/.bashrc  # or source ~/.zshrc

If you installed with pipx:

# Add pipx bin directory to PATH
pipx ensurepath

# Then restart your terminal OR reload:
source ~/.bashrc  # for bash
source ~/.zshrc   # for zsh

After running pipx ensurepath, you should see a message that PATH was updated. Restart your terminal to apply changes.

Windows:

• Add C:\Users\YourName\AppData\Local\Programs\Python\Python3xx\Scripts to PATH
• Or restart your terminal/command prompt

"Already installed but still shows old version"

If you're using Anaconda, see the Special Note for Anaconda Users section above.

For regular users, check which Python is being used:

which python3      # Linux/macOS
where python       # Windows

Installation fails with "File exists" error

This happens with Anaconda. Use this instead:

pip install --user .    # Instead of: pip install --user -e .

The difference:

• pip install . - Regular installation (recommended)
• pip install -e . - Editable/development mode (may conflict with Anaconda)

Import errors

If you get import errors, install dependencies manually:

pip install requests beautifulsoup4 packaging click

Permission errors (Linux/macOS)

Some operations require elevated privileges:

sudo pyvm update

Windows installer issues

• Make sure you have administrator privileges
• Temporarily disable antivirus if installer is blocked
• Download manually from https://www.python.org/downloads/

"Python updated but I still see the old version"

This is normal! The new Python is installed alongside your old version:

# Check all installed Python versions
ls /usr/bin/python*           # Linux/macOS
py --list                     # Windows

# Use the new version specifically
python3.14 --version          # Linux/macOS
py -3.14 --version           # Windows

Want to make the new Python your default? See the detailed guide: Making Updated Python the Default

Development

in the Option for Advanced Users: Change System Default section.

Development

# Clone the repository
git clone https://github.com/shreyasmene06/pyvm-updater.git
cd pyvm-updater

# Install in editable mode
pip install -e .

# Run tests (if available)
python -m pytest

Running Tests

# Run all tests
python -m pytest

# Run with coverage
python -m pytest --cov=pyvm_updater

# Run specific test file
python -m pytest tests/test_specific.py

Contributing

Contributions are welcome and appreciated. To contribute:

1. Fork the repository
2. Create a feature branch (git checkout -b feature/your-feature-name)
3. Make your changes and commit them with clear, descriptive messages
4. Write or update tests as needed
5. Ensure all tests pass
6. Push to your fork (git push origin feature/your-feature-name)
7. Open a Pull Request with a clear description of your changes

Contribution Guidelines

• Follow PEP 8 style guidelines for Python code
• Add tests for new features
• Update documentation as needed
• Keep commits focused and atomic
• Write clear commit messages

For more details, see CONTRIBUTING.md

License

This project is licensed under the MIT License. See the LICENSE file for details.

Author

Shreyas Mene

Disclaimer

This tool downloads and installs software from python.org. Always verify the authenticity of downloaded files. The authors are not responsible for any issues arising from Python installations.