Repeat items in list to required length

Question

I have a list of available items that I can use to create a new list with a total length of 4. The length of the available item list never exceeds 4 items. If the list has less than 4 elements I want to populate it with the available elements beginning at the start element.

Example 1:

available_items = [4, 2]
Result -> [4, 2, 4, 2]

Example 2:

available_items = [9, 3, 12]
Result -> [9, 3, 12, 9]

Example 3:

available_items = [3]
Result -> [3, 3, 3, 3]

I have the feeling that my solution is not optimal, but I have found nothing better so far:

available_items = [3, 5]
required_items = 4

if len(available_items) == 1:
  new_items = [available_items[0]] * required_items
else:
  new_items = available_items + []
  for i in range(required_items - len(available_items)):
    new_items.append(available_items[i])

print(new_items)

Answer 1

You can use itertools.cycle

Ex:

from itertools import cycle

available_items_1 = cycle([4, 2])
available_items_2 = cycle([9, 3, 12])
available_items_3 = cycle([3])

n = 4

print([next(available_items_1)for i in range(n)])
print([next(available_items_2)for i in range(n)])
print([next(available_items_3)for i in range(n)])

Output:

[4, 2, 4, 2]
[9, 3, 12, 9]
[3, 3, 3, 3]