'dict_keys' object is not subscriptable

This error occurs when you try to access an element of a dictionary using square brackets [], but you mistakenly use a dict_keys object instead of a dictionary.

A dict_keys object is a view object that provides a dynamic view of the keys of a dictionary. It is not a dictionary itself, so you cannot access its elements using square brackets.

To fix this error, you need to convert the dict_keys object into a list or another data type that can be subscripted. For example:

my_dict = {'a': 1, 'b': 2, 'c': 3}
keys = my_dict.keys()  # dict_keys(['a', 'b', 'c'])
key_list = list(keys)  # ['a', 'b', 'c']
print(key_list[0])  # Accessing the first key using square brackets

In this example, we convert the dict_keys object into a list and then access its elements using square brackets.