input: Write a function to find the largest three numbers in a list. The function should return a list containing the three largest numbers in descending order. If the list has fewer than three numbers, it should return all the numbers in descending order.
  assert find_largest_three([1, 6, 3, 8, 7, 4])==[8, 7, 6]
  assert find_largest_three([10, 20])==[20, 10]
  assert find_largest_three([5])==[5]
  assert find_largest_three([])==[]
  assert find_largest_three([1, 2, 3, 4, 5])==[5, 4, 3]
output: def find_largest_three(nums):
      return sorted(nums, reverse=True)[:3]