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List, Tuple, Dictionary, Set

• Two ways to Create Lists: 1. Using square brackets [], like colors = ["red", "green", "blue"]. 2. Using the list() constructor, like numbers = list((1, 2, 3)).

• Accessing Elements: Access list elements using positive or negative indexing, such as games[0] and games[-1].

• Slicing Lists: Get sub-lists using [start:end], like months[1:3], months[:2], and months[3:].

• Adding Items: Use append() to add an element to the end of the list, like todo.append("brush teeth"). Use insert() to insert an element at a specified position, like todo.insert(1, "make bed").

• Removing Items: Use remove() to remove an element by its value, like pets.remove("dog"). Use pop() to remove the last element or an element at a specified position, like last = pets.pop().

• Sorting Lists: Use the sort() method to sort the list, like scores.sort(). You can sort in descending order using the reverse=True parameter, like scores.sort(reverse=True).

• Tuples vs Lists: Tuples are immutable, while lists are mutable. Tuples use parentheses (), and lists use square brackets [].

• Two ways to Create Dictionaries: 1. Using curly braces {}, like student = {"name": "Emma", "age": 20, "major": "CS"}. 2. Using the dict() constructor, like colors = dict(red="#FF0000", green="#00FF00").

• Adding & Changing Entries: Add or update values in the dictionary using keys, like animal_sounds["dog"] = "Woof!".

• Removing Entries: Use del to delete entries in the dictionary, like del animal_sounds["dog"].

• Safe Value Access with get(): Use the get() method to access values in the dictionary, and return a default value if the key does not exist.

• Dictionary Methods Summary: my_dict.keys(): Get all the keys in the dictionary. my_dict.values(): Get all the values in the dictionary. my_dict.items(): Get all the key-value pairs in the dictionary.

• Two ways to Create Sets: 1. Using curly braces {}, like colors = {"red", "green", "blue"}. 2. Using the set() constructor, like numbers = set([1,2,3,3]).

• Set intersection: Use & to get the intersection of two sets, like both = art_students & music_students.

• Set union: Use | to combine two sets, like all_customers = week1_customers | week2_customers.

• Set difference: Use - to get elements in one set that are not in another, like remaining = available_colors - used_colors.

• Set Methods: aadd(): Add an element. remove(): Remove an element.