# Custom Python interpreter

You can specify a Python interpreter that is different from the interpreter that is bundled with the distribution.

For example, due to constraints or requirements of some Linux operating systems, you might need to use the version of Python that is installed on your system. For more information about system requirements and their installed Python versions, see the Spotfire Service for Python system requirements.

If you want to use the system-installed Python interpreter in a containerized system, see Configuring a custom Docker image on a node with internet access.

To use the system-installed Python interpreter, or another compatible Python interpreter that is different from the interpreter bundled with the Spotfire Service for Python, you must meet the following prerequisites.

## Prerequisites for using a custom Python interpreter

- Ensure that Python version 3.9.x or higher is installed on the system.
- Set the environment variable `SPOTFIRE_PYTHON_HOME` to the path to the directory for the installed Python interpreter that you want to use.
  - On Linux, the Spotfire Service for Python uses and searches for <SPOTFIRE_PYTHON_HOME>/bin/python3.
  - On Windows, the Spotfire Service for Python searches for <SPOTFIRE_PYTHON_HOME>/python.exe
- Install the spotfire Python package (available at https://pypi.org/project/spotfire/).

Note: The environment variable `SPOTFIRE_PYTHON_HOME` must be accessible to the running node manager.

- For Linux, you can establish this connection with the file start-python-service.sh (located at /opt/spotfire/nodemanager/<version>/nm/services/python-service-linux-<guid>/start-python-service.sh).
- For Windows, you can set this connection with the file startPython.bat (located at C:/spotfire/nodemanager/<version>/nm/services/Python Service Windows-<guid>/startPython.bat).