inversions.py

def make_permutation(n=4):
  result = []
  for i in range(1, n+1):
    result.append(i)

  return result

def get_all_pairs(permutation=make_permutation()):
  pairs = []
  for i in range(0, len(permutation)):
    for j in range(0, len(permutation)):
      if i == j:
        continue
      else:
        pairs.append([permutation[i], permutation[j]])

  return pairs

def count_inversions(pairs=get_all_pairs()):
  count = 0
  for pair in pairs:
    if pair[0] > pair[1]:
      count += 1

  return count


permutation = make_permutation(n=4)
all_pairs = get_all_pairs(permutation)
inversions_count = count_inversions(all_pairs)

print(inversions_count)