c = filter(lambda x: x>=3, map(lambda x: x+x, (1, 2, 3, 4)))
print(list(c))

def unpacking(x, y, z):
    print(x, y, z, end=" ")
tuple_vec = (1, 0, 1)
dict_vec = {'x': 1, 'y': 0, 'z': 1}
unpacking(*tuple_vec)
unpacking(**dict_vec)

7//3 + 7//-3

class B:
    def __init__(self):
        self.arr = []
    def __getattr__(self, attrname):
        return getattr(self.arr, attrname)
    
b = B()
b.append(1)
b.append(2)
b.append(3)
b.pop()
print(b.arr)

",".join(['1', '2', '3', '4'])

print(type(type(bool(1))))

x = float('inf')
s = x - x
print(s)

import numpy as np
import pandas as pd
a = pd.np.array([1, 2, 3])
b = np.array([-3, 2, 1])
print(a @ b)

print(list(map(lambda f: f(2), [lambda x: x**i for i in range(3)])))

print(list(map(lambda f: f(2), (lambda x: x**i for i in range(3)))))