'NoneType' object is not iterable

This error occurs when you try to iterate over a variable or object that has a value of None. None is a special value in Python that represents the absence of a value.

For example, if you have a function that returns None instead of a list or tuple, and you try to loop over the result of that function, you will get the 'NoneType' object is not iterable error.

To fix this error, you need to make sure that the variable or object you are trying to iterate over is not None. You can do this by checking if the variable is None before attempting to iterate over it.

Here's an example:

my_list = some_function_that_returns_none()

if my_list is not None:
    for item in my_list:
        # do something with item
else:
    # handle the case where my_list is None

In this example, we first check if my_list is not None. If it is not None, we can safely iterate over it. If it is None, we can handle that case separately.