Real Python - Dictionaries in Python by John Sturtz

Here's what you'll learn in this course: You'll cover the basic characteristics of Python dictionaries and learn how to access and manage dictionary data. Once you've finished this course, you'll have a good sense of when a dictionary is the appropriate data type to use and know how to use it.
Dictionaries and lists share the following characteristics:
Both are mutable.
Both are dynamic. They can grow and shrink as needed.
Both can be nested. A list can contain another list. A dictionary can contain another dictionary. A dictionary can also contain a list, and vice versa.
Dictionaries differ from lists primarily in how elements are accessed:
List elements are accessed by their position in the list, via indexing.
Dictionary elements are accessed via keys.
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https://realpython.com/courses/dictionaries-python/