what is a dictionairy of dictionairies in python code example

Example 1: dict of dict python

nested_dict = { 'dictA': {'key_1': 'value_1'},
                'dictB': {'key_2': 'value_2'}}

Example 2: make nested dict from two dict

data = [
    [14, 77766, [2, 2]],
    [15, 77766, [1, 2]],
    [70, 88866, [1, 5]],
    [71, 88866, [2, 5]],
    [72, 88866, [5, 5]],
    [73, 88866, [4, 5]],
    [74, 88866, [3, 5]],
    [79, 99966, [1, 2]],
    [80, 99966, [2, 2]],
]

c = {}
for key, id_, (value, _) in data:
    c.setdefault(id_, {})[key] = value
print(c)