Grequests not returning all items

Question

I have the following code:

>>> import grequests
>>> urls=[
     'https://www.microsoft.com/en-us/store/movies/the-legend-of-blood-castle/8d6kgwzzx9hm', 
     'https://www.microsoft.com/en-us/store/movies/babe/8d6kgwzl64t3']
>>> rs = (grequests.get(url) for url in urls)
>>> res_items=grequests.map(rs)
>>> res_items
[<Response [200]>]

However, it should return:

[<Response [200]>, <Response [404]>]

But for whatever reason, it's not doing anything with the 404. Why is this so, and what do I need to do for the 404 to appear in the results?