PyPyPath

Module 5: Lists in Python

List Methods

Lists have helpful methods to add, remove, and sort items. You call them with a dot: my_list.method().

About 12 minutes

Adding items

Example code
items = ["pen"]
items.append("pencil")   # add to end
print(items)

items.insert(0, "eraser")  # add at index 0
print(items)

Removing items

Example code
nums = [1, 2, 3, 2]
nums.remove(2)   # removes first 2 found
print(nums)

last = nums.pop()  # removes and returns last
print(last, nums)

Sorting

Example code
scores = [85, 92, 78]
scores.sort()       # sorts in place
print(scores)

print(len(scores))  # count items
Practice

Start with [3,1,4]. Append 1, sort, then print the list.

Key takeaways

  • append() adds to the end; insert() adds at a position.
  • remove() deletes a value; pop() removes the last (or at index).
  • sort() orders the list in place.

Quick check: List Methods

Question 1 of 2

Which method adds one item to the end?