Is there another way to iterate through only the attributes of a custom class that are not in-built (e.g. __dict__, __module__, etc.)? For example, in this code:

class Terrain:
    WATER = -1
    GRASS = 0
    HILL = 1
    MOUNTAIN = 2

I can iterate through all of these attributes like this:

for key, value in Terrain.__dict__.items():
    print("{: <11}".format(key), " --> ", value)

which outputs:

MOUNTAIN     -->  2
__module__   -->  __main__
WATER        -->  -1
HILL         -->  1
__dict__     -->  <attribute '__dict__' of 'Terrain' objects>
GRASS        -->  0
__weakref__  -->  <attribute '__weakref__' of 'Terrain' objects>
__doc__      -->  None

If I just want the integer arguments (a rudimentary version of an enumerated type), I can use this:

for key, value in Terrain.__dict__.items():
    if type(value) is int: # type(value) == int
        print("{: <11}".format(key), " --> ", value)

this gives the expected result:

MOUNTAIN    -->  2
WATER       -->  -1
HILL        -->  1
GRASS       -->  0

Is it possible to iterate through only the non-in-built attributes of a custom class independent of type, e.g. if the attributes are not all integral. Presumably I could expand the conditional to include more types, but I want to know if there are other ways I'm missing.