Bisection module allows you to efficiently add items to a sorted list so that you don't have to resort it.

import bisect

numbers = [1, 2, 4, 8]

bisect.insort(numbers, 5)
assert numbers == [1, 2, 4, 5, 8]

bisect.insort(numbers, 5)
assert numbers == [1, 2, 4, 5, 5, 8]

# but it won't work if the list is not sorted
integers = [4, 5, 3, 8]
bisect.insort(integers, 4)
assert integers == [4, 5, 3, 4, 8]  # doesn't really do much, eh

Useful in two main cases:

• the list is massive
• the comparison operation is expensive

Source

• Python 3 Documentation