Lists & Tuples

Lists are ordered collections. Create with brackets. Tuples are fixed ordered collections; create them with parentheses when you want a stable pair, coordinate, or small record:

items = [1, 2, 3]
empty = []
mixed = ["hello", 42, True]
point = (12, 8)
single = (42,)

Access by index (0-based, negative from end):

first = items[0]    # 1
last = items[-1]    # 3
x = point[0]        # 12

Slicing with step:

items[1:3]     # [2, 3]
items[::2]     # [1, 3]  every other
items[::-1]    # [3, 2, 1]  reversed
point[:]       # (12, 8)

List comprehension builds lists concisely:

squares = [x * x for x in range(10)]
evens = [x for x in range(20) if x % 2 == 0]

Tuple unpacking and multiple assignment:

a, b, c = [1, 2, 3]
first, second = ("hello", "world")

def choose_route():
    return "E14", ["E13", "E14"]

target, route = choose_route()

routes = [(0, "nav_module"), (1, "cargo_rack")]
for slot, item in routes:
    print(slot, item)

Ternary expression:

status = "hot" if heat > 50 else "cool"

List methods

Method	Purpose
`.append(value)`	add to end
`.pop()`	remove and return last item
`.insert(index, value)`	insert at position
`.remove(value)`	remove first occurrence
`.index(value)`	find position of value
`.count(value)`	count occurrences
`.sort()`	sort in place
`.reverse()`	reverse in place
`.copy()`	shallow copy
`.extend(list_or_tuple)`	add all items from another sequence
`.clear()`	remove all items
`.length`	number of items (property)

Tuples are immutable. They support indexing, slicing, .index(value), .count(value), .length, len(), and for loops.

Lists & Tuples

List methods

See also