2. Working with Data

Abstraction: Python data structures tutorial covering lists, tuples, sets, dicts, comprehensions

Key points:

• Lists support negative indexing, slicing with optional step (x[::-1] reverses), and in-place sort with optional key function
• Tuples are immutable sequences; single-element tuples require trailing comma (1,)
• Sets offer O(1) membership testing via in; faster than lists for existence checks
• List comprehensions support filtering (if clause), multi-list iteration with zip, and nested for clauses
• Dictionaries support get(key, default), setdefault, and named string formatting with %(name)s
• Word frequency counting pattern: frequency[w] = frequency.get(w, 0) + 1

Connections: Python · Data Structures · List Comprehensions

Source: http://anandology.com/python-practice-book/working-with-data.html#list-comprehensions