The pprint() code has a number of type or protocol specific handlers but doesn't have one for dict views.  So, we don't get pretty printing for the key(), values(), and items():

d = {i:i for i in range(100)}
pprint(d)             # This is handled correctly
pprint(d.keys())      # Printed on one line
pprint(d.values())    # Printed on one line
pprint(d.items())     # Printed on one line