list_sizes does not return a full list of available AWS instances

[simonm3]

I am using version 3.8 in aws region eu-west-1. When I call list_sizes() the returned list does not include p2.xlarge instances. My colleague on a different computer (possibly using older version) does have p2.xlarge but does not have any from the c6i instances range.

In both cases the list is incomplete but in different ways. Am I missing something?