new_contents: # short code for day 7, since I spent
  # ages setting up my Jekyll page.
  
  def list_averages(*lists):
      avg_sum = 0
      avg_len = 0
      for l in lists:
          avg_sum += list_sum(l)
          avg_len += list_len(l)
      avg_sum /= list_len(lists)
      avg_len /= list_len(lists)
      
      return [avg_sum, avg_len]
  
  def list_sum(l):
      x = 0
      for i in l:
          x += i
      return x
  
  def list_len(l):
      x = 0
      for i in l:
          x += 1
      return x
  
  # TEST CASES:
  a = [3, 9, 12, 6, 90, 2]
  b = [17, 5, 81, 4, 55]
  c = [4, 4, 90, 28]
  
  print(list_averages(a, b, c))
  # => [136, 5]
  
  print(list_averages(a, b))
  # => [142, 5]
  
  print(list_averages(a, c))
  # => [124, 5]
  
  print(list_averages(b, c))
  # => [144, 4]
  
  
subject: Create averages.py