TypeError: type 'str' is not subscriptable

This error occurs when you try to use square brackets to access elements of a string, but the string itself is not a subscriptable object. Subscriptable objects include lists, tuples, and dictionaries, but not strings.

For example, if you have a string variable called "my_string" and you try to access the first character using my_string[0], you will get this error if "my_string" is actually a string and not a list or tuple.

To avoid this error, make sure you are using subscripting only on objects that are subscriptable, such as lists or tuples. If you need to access individual characters in a string, you can convert the string to a list first, then use subscripting on the list. Alternatively, you can use string methods like "split" and "join" to manipulate the string without subscripting.