from collections import defaultdict
d = defaultdict(list)
d['a'].append(1)
d['a'].append(2)
d['b'].append(3)
sum((len(d['a']*3), len(d['b'])*5))

from sys import getsizeof
from collections import OrderedDict
d1 = dict(a1=1, b=2)
d2 = OrderedDict(a=1, b=2)
s1 = getsizeof(d1)
s2 = getsizeof(d2)

from collections import OrderedDict
d = OrderedDict()
d['a'] = 0
d['b'] = 1
d['a'] = 2
s = [*d.keys()][-1]
print(s)

d = {"a": 2, "b": 3, "c": 2}
s = zip(d.values(), d.keys())
a = len([*s])
b = len([*s])
print(a, b)

d = {"a": 2, "b": 3, "c": 2}
f = lambda: zip(d.values(), d.keys())
max_ = max(f())
min_ = min(f())
print(max_, min_)

d1 = {"x": 1, "y": 2}
d2 = {"y": 2, "z": 3}
r1 = d1.keys() & d2.keys()
r2 = d1.keys() - d2.keys()
print(*r1, *r2)

d1 = {"x": 1, "y": 2}
d2 = {"y": 2, "z": 3}
print(*(d1.items() - d2.items()))

d1 = {"x": 1, "y": 2}
d2 = {"y": 2, "z": 3}
print(d1.values() - d2.values())

a = [1, 5, 2, 1, 1, 5]

def f(items):
    s = set()
    for item in items:
        if item not in s:
            yield item
            s.add(item)
print(*f(a))

def f(items, key=None):
    s = set()
    for item in items:
        val = item if key is None else key(item)
        if val not in s:
            yield item
            s.add(val)
arr = [1.1, 1.2, 2.1, 3.0]
y = f(arr, key=lambda d: sum([int(x) for x in str(d).split(".")]))
print(*y)