a = 256
b = 256
c = 257
d = 257
print(a is b, c is d)

gen = (x for x in range(3))
a = list(gen)
b = list(gen)
print(a, b)

def modify(x, y=[]):
    y.append(x)
    return sum(y)

result = modify(5) + modify(7) + modify(4)
print(result)

def modify(x, y=[]):
    y.append(x)
    return sum(y)

result = modify(5) + modify(7) + modify(4)
print(result)

from itertools import islice

def infinite_seq():
    n = 1
    while True:
        yield n
        n *= 2

gen = infinite_seq()
result = list(islice(gen, 5))
print(sum(result))

def modify(x, y=[]):
    y.append(x)
    return sum(y)

result = modify(5) + modify(7) + modify(4)
print(result)

gen = (x for x in range(3))
print(list(gen), list(gen))

x = [0, 1]
i = 0
i, x[i] = 1, 2
print(x)

class A:
    def __new__(cls):
        return 42
        
    def __init__(self):
        print("Init")

print(A())

gen = (x for x in range(3))
print(list(gen), list(gen))