from collections import Counter, defaultdict

def mode(seq):
    c = Counter(seq)
    x, amount = c.most_common(1)[0]
    return [k for k, v in c.items() if v == amount]

def separate_by_type(seq):
    d = defaultdict(list)
    for item in seq:
        d[type(item)].append(item)
    return d

x = [1.0, 2.0, 2.0, 2, 1, 3, 3, 4, 4]
d = separate_by_type(x)
for t, seq in d.items():
    print(f"Mode of items with type {t}:")
    print(mode(seq))

#output:
#Mode of items with type <class 'float'>:
#[2.0]
#Mode of items with type <class 'int'>:
#[3, 4]