TypeError: 'NoneType' object is not subscriptable

This error occurs when you try to access a subscriptable object (e.g., a list, string, or dictionary) using the square bracket notation, but the object is actually of type NoneType, which means it has no value or is not defined.

For example, if you try to access an element of a list that has not been initialized or is set to None:

my_list = None
print(my_list[0])

This will raise the TypeError because you are trying to access the first element of a NoneType object.

To fix this error, you need to ensure that the object you are trying to access using square bracket notation is not None. You can do this by initializing the object with a valid value or checking if it is None before accessing it.