How to add new keys to a dictionary in Python?

Dictionary is an unordered collection of key-value pairs. Each element is not identified by positional index. Moreover, the fact that key can’t be repeated, we simply use a new key and assign a value to it so that a new pair will be added to dictionary.

>>> D1 = {1: 'a', 2: 'b', 3: 'c', 'x': 1, 'y': 2, 'z': 3}
>>> D1[10] = 'z'
>>> D1
{1: 'a', 2: 'b', 3: 'c', 'x': 1, 'y': 2, 'z': 3, 10: 'z'}