text: import time
  
  a = dict()
  b = list()
  for i in range(10000000):
      a[i] = i
      b.append(i)
  
  
  sum = 0
  time1 = time.time()
  
  for i in a.keys():
      sum += i
  
  print('dict time:', time.time() - time1)
  
  
  sum = 0
  time2 = time.time()
  
  for i in b:
      sum += i
  
  print('list time:', time.time() - time2)
  