How to Change Default Python Version from 3.5 to 3.8 in Google Colab: A Step-by-Step Guide

Knowing how to change the Python version from the default 3.5 to 3.8 in Google Colab is crucial for several reasons. It ensures compatibility with newer libraries and frameworks, which often require Python 3.8. This is particularly important for projects involving machine learning or data science, where using the latest tools can significantly enhance performance and capabilities. Additionally, some legacy code or specific project requirements might necessitate a particular Python version to function correctly. Understanding this process allows for greater flexibility and efficiency in your coding environment.

Checking the Current Python Version

Here are the steps:

1. Open Google Colab and create a new notebook.
2. Insert a new code cell.
3. Type the command !python --version in the code cell.
4. Run the cell by clicking the “Run” button or pressing Shift + Enter.
5. Check the output below the cell for the current Python version.

That’s it!

Changing the Python Version

Sure, here are the steps to change the Python version from 3.5 to 3.8 in Google Colab:

1. Open a new or existing Colab notebook.
2. Run the following commands in a code cell:

# Install Python 3.8
!sudo apt-get update -y
!sudo apt-get install python3.8

# Update alternatives to point to Python 3.8
!sudo update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.5 1
!sudo update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.8 2

# Check the Python version
!python3 --version

3. Restart the runtime to apply the changes.

This will set Python 3.8 as the default Python version for your current Colab session. If you need to switch back to Python 3.5 or another version, you can adjust the update-alternatives command accordingly.

Verifying the Change

1. Open a new code cell in Google Colab.
2. Type !python --version and run the cell.
3. Verify the output shows Python 3.8.x.

Alternatively, use:

import sys
print(sys.version)

The output should start with 3.8.

Common Issues and Troubleshooting

Here are common issues and troubleshooting tips for changing the Python version in Google Colab:

Common Issues

1. Library Compatibility:

   • Issue: Some libraries may not be compatible with the new Python version.
   • Tip: Check and update libraries using !pip install --upgrade <library>.

2. Environment Variables:

   • Issue: Environment variables might not be set correctly for the new Python version.
   • Tip: Manually set environment variables using os.environ.

3. Kernel Crashes:

   • Issue: The Colab kernel may crash after changing the Python version.
   • Tip: Restart the runtime from the “Runtime” menu.

4. Path Conflicts:

   • Issue: Multiple Python versions might cause path conflicts.
   • Tip: Use !sudo update-alternatives --config python3 to set the correct path.

5. Dependency Issues:

   • Issue: Dependencies required by the new Python version might be missing.
   • Tip: Install missing dependencies using !apt-get install <dependency>.

6. Virtual Environment Problems:

   • Issue: Virtual environments might not work correctly with the new Python version.
   • Tip: Create a new virtual environment using !python -m venv <env_name>.

7. Script Errors:

   • Issue: Scripts might fail due to syntax or deprecated functions in the new version.
   • Tip: Update your code to be compatible with the new Python version.

Troubleshooting Tips

• Check Python Version: Use !python --version to verify the current Python version.
• Reinstall Libraries: After changing the Python version, reinstall essential libraries using !pip install <library>.
• Use Specific Python Version: Run specific Python versions using !python3.x script.py.
• Update Alternatives: Use !sudo update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.x 1 to set the default Python version.

To Change the Python Version in Google Colab

To change the Python version from the default 3.5 to 3.8 in Google Colab, follow these steps:

1. Open a new or existing Colab notebook and run the following commands in a code cell:

!sudo apt-get update -y
!sudo apt-get install python3.8

2. Update alternatives to point to Python 3.8:

!sudo update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.5 1
!sudo update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.8 2

3. Check the Python version:

!python3 --version

4. Restart the runtime to apply the changes.

This will set Python 3.8 as the default Python version for your current Colab session. If you need to switch back to Python 3.5 or another version, adjust the update-alternatives command accordingly.

Why Change the Python Version?

Changing the Python version in Google Colab is crucial for several reasons:

• It ensures compatibility with newer libraries and frameworks, which often require Python 3.8.
• Some legacy code or specific project requirements might necessitate a particular Python version to function correctly.
• Understanding this process allows for greater flexibility and efficiency in your coding environment.

Common Issues When Changing the Python Version

Being able to switch Python versions as needed is essential for several reasons:

• It ensures compatibility with newer libraries and frameworks, which often require the latest Python version.
• Some legacy code or specific project requirements might necessitate a particular Python version to function correctly.
• Understanding this process allows for greater flexibility and efficiency in your coding environment.

Common issues that may arise when changing the Python version include:

• Library compatibility
• Environment variables not being set correctly
• Kernel crashes
• Path conflicts
• Dependency issues
• Virtual environment problems
• Script errors

Troubleshooting Tips

Troubleshooting tips include:

• Checking the Python version
• Reinstalling libraries
• Using specific Python versions
• Updating alternatives
• Manually setting environment variables