zero_suffix.py

def rindex_func(func, l):
    for (i,obj) in reversed(list(enumerate(l))): ## Boo! list()
        if func(obj):
            return i
    return None

def only_as_suffix(obj, l):
    try:
        i = l.index(obj)
    except ValueError:
        return True
    
    j = rindex_func(lambda x: x != obj, l)
    if j:
        return j < i
    else:
        return True

print only_as_suffix(0, [0,0]) # True
print only_as_suffix(0, [1,2,3,4]) # True
print only_as_suffix(0, [1,2,3,4,0]) # True
print only_as_suffix(0, [1,2,3,4,0,0,0]) # True
print only_as_suffix(0, [1,2,0,3,4,0]) # False