Iterator _ Study Notes

. 1  # the Author: CallMeV 
2  # DATE: 2019-11-10 
. 3  # Time: 10:43 
. 4  
. 5  # create iterators 
. 6 L = [1,2,3,4 ]
 . 7 D = ITER (L) # <list_iterator Object AT 0x000002AEA4DD4490> 
. 8  Print (D)
 . 9  Print (Next (D))
 10  Print (Next (D))
 . 11  Print (Next (D))
 12 is  Print (Next (D))
 13 is  
14  
15  # for loop do three things: 
16  #      1, calls iter method returns an iterable 
17  #     2, the continuous iterative call to the next object can be 
18  #      3, the process StopInteration 
. 19  for I in [1,2,3,4 ]:
 20 is      Print (I)
 21 is  
22 is  from Collections Import the Iterator
 23 is  Print (the isinstance ([1,2 ], List))
 24  Print (the isinstance (L, the Iterator))
 25  Print (the isinstance (D, the Iterator))

Iterator satisfy two conditions: 1 Method 2 has the next method has iter