name 'colorbar' is not defined

The error message you encountered, "name 'colorbar' is not defined," typically occurs when you try to use the `colorbar` function in Python without importing the necessary module. The `colorbar` function is part of the `matplotlib` library, so you need to import it before using it.

To fix this issue, you can add the following import statement at the beginning of your code:

import matplotlib.pyplot as plt

This will import the `matplotlib.pyplot` module, which includes the `colorbar` function. Make sure you have `matplotlib` installed in your environment as well.