def find_best_seed(sample):
  """
  In the list of seeds in sample, find the seed (not necessarily
  unique) with maximum fitness.
  """
  sample_size = len(sample)
  assert sample_size > 0
  best_seed = sample[0]
  best_score = best_seed.fitness()
  for i in range(len(sample)):
    if (sample[i].fitness() > best_score):
      best_seed = sample[i]
      best_score = best_seed.fitness()
  return best_seed