How do you set environment variables in Python?

There are several ways to set environment variables in Python.

1. Set environment variables through the command line of the operating system.
2. In Windows system, you can use the command set or set in system properties.
3. In Linux/Mac systems, you can use the command export.
4. Below is an example code that demonstrates how to set environment variables in a Python script using the os module.
5. Set the value of the environment variable ‘MY_VARIABLE’ to ‘my_value’.
6. In a Python virtual environment, you can set environment variables by configuring them in the activate script of the virtual environment.

Please note that regardless of the method used to set the environment variables, the relevant applications need to be restarted in order for the changes to take effect.