class A:
    x = 1
    def __init__(self):
        self.y = 2

a = A()

class A:
    def __iter__(self):
        yield from range(10)
a = A()
print(5 in a, 20 in a)

def g(f1, f2, x):
    return f1(x) + f2(x) if x else 0
f1, f2 = lambda x: x**3/abs(x), lambda x: x % 2
x = 121
g(f1, f2, -x) + g(f1, f2, x)

import re
sent = 'Hello, Ben! How are you doing?'
lister = filter(None, re.split("[,!?]+", sent))
print(len(list(lister)))

from itertools import product
a = [1, 2]
b = [3, 4]
sum(sum(product(a, b), (0, 0)))

def f(x):
    try:
        print('1', end=" ")
        y = 1 * 0 if x % 2 else 1 / 0
    except:
        y = 0
        print('2', end=" ")
    else:
        print('3', end=" ")
    finally:
        print('4', end=" ")
    return y

print(f(1) + f(2))

class A:
    def __init__(self, x=0):
        self.x = x
    def f(self):
        print(self.x)
a = A(2020)
f = a.f
print(f.__self__ is a, end=" ")
print(f.__func__ is f, end=" ")
print(f.__func__ is a.f, end=" ")
print(f.__func__ is A.f, end=" ")

import numpy as np
print(np.asarray([100, 200, 300]).astype(np.int8))

import numpy as np
print(np.uint8(1 - 2))

import numpy as np
mat = np.array([[1, 2], [4, 5]])
print(round((mat @ np.linalg.inv(mat)).sum()))