input: Write a python function to sort a list of numbers in ascending order using bubble sort.
  assert sort_nums([34, 7, 23, 32, 5, 62]) == [5, 7, 23, 32, 34, 62]
  assert sort_nums([1, 2, 3, 4, 5]) == [1, 2, 3, 4, 5]
  assert sort_nums([10, 9, 8, 7, 6]) == [6, 7, 8, 9, 10]
output: def sort_nums(arr):
      n = len(arr)
      for i in range(n):
          for j in range(0, n-i-1):
              if arr[j] > arr[j+1]:
                  arr[j], arr[j+1] = arr[j+1], arr[j]
      return arr