def f(*seqs, pad=None):
    maxlen = max(len(S) for S in seqs)
    index = range(maxlen)
    return [tuple((S[i] if len(S) > i else pad) for S in seqs) for i in index]
s1, s2 = 'ab' , 'xyz'
print(f(s1, s2))

def mymap(func, *seqs):
    res = []
    for args in zip( *seqs):
        res.append(func( *args))
    return res
x = [1, 2, 3]
y = [2, 3, 4, 5]
a = mymap(pow, x, y)
b = [*map(pow, x, y)]
print(a == b)

def f(seq):
    for i in range(len(seq)):
        seq = seq[1:] + seq[:1]
        yield seq
print(''.join(list(f('xy'))))

class MyExc(Exception): pass 
def f():
    raise MyExc()
    return  'f'
try:
    print(f())
    print('try')
except MyExc:
    print('exc')

x = 0
try:
    1/0
    x += 1
except ZeroDivisionError:
    x += 1
else: 
    x += 1
    1/0
    x += 1
print(x)

try:
    print('try')
    1/0
else:
    print('else')

x = 0
try:
    x += 1
except ZeroDivisionError:
    x += 1
else: 
    x += 1
    1/0
    x += 1
print(x)

d = {'a': 1, 'b': 2, 'c': 3}
x = [string for string, digit in d.items() if digit > 1]
print(x)

sum([1 << i for i in range(5)])