l1 = [1, 8, 7, 2, 21, 15]
print(l1)

# l1.sort()  # sort the list
# l1.reverse()  # reverses the list
# l1.append(45)  # appends the list
# l1.insert(2, 544)  # insert 544 at index 2
# l1.pop(2)  # remove element at index 2
l1.remove(21)  # removes 21 from list
print(l1)
