Python generator on dictionary view does not seem to be lazily evaluated -


It is my understanding that dragon generator expressions have returned the expression expressions of light, and their underlying dictionary changed But see the objects on the dictionaries of dictionaries. / P>

Looking at the following code (Windows Python 2.7.6): 

  d = {} gt_three = (x for x in d.viewkeys ()) If x & Gt; 3) Print list (gt_three) D [1] = 'A' D [4] = 'Four' print list (gt_three)   
 I think the output is expected as follows: Instead, I'm getting:  > If I prepare the generator after adding it to the dictionary, or print the view itself, So I see the expected output. What I can not understand about the generator? I am new to Python.   
 
 
 A generator expression gives an Iterator, which you can only repeat once. After the first attempt to iterate over an iterator, it will always appear empty.

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