Kush1101

def prefix_of_list(array):
    ans = [[]]
    prev = ans[-1]
    for i in range(len(array)):
        ans.append(prev + array[i])
    return ans
        

Kush1101

from itertools import zip_longest

iter1 = [1, 2, 3, 4, 5, 6]
iter2 = [1, 4, 9, 16, 25]
iter3 = [1, 8, 27, 64, 125]

for i in zip_longest(iter1, iter2, iter3, fillvalue = 0):
    print(i)
# OUTPUT
"""

Kush1101

from itertools import tee

iterable = [1, 2, 4, 6, 7, 13]
for i in tee(iterable, 4):
    print(list(i))
# OUTPUT
"""
[1, 2, 4, 6, 7, 13]
[1, 2, 4, 6, 7, 13]
[1, 2, 4, 6, 7, 13]

Kush1101

from itertools import takewhile

iterable = [1, 3, 5, 7, 2, 4, 6, 9, 11]
predicate = lambda x: x%2==1

for i in takewhile(predicate, iterable):
    print(i, end = ' ')
# OUTPUT
"""
1 3 5 7

Kush1101

from itertools import groupby

a_list = [("Even", 2), 
		("Odd", 5), 
		("Even", 8), 
		("Odd", 3)]
 
iterator = groupby(a_list, key = lambda x:x[0]) 

for key, group in iterator: 

Kush1101

from itertools import starmap
from operator import add, mul
iterable = [(1,3), (2,4), (3,0), (5,6)]

for i in starmap(add, iterable):
    print(i, end = ' ')
# 4 6 3 11

for i in starmap(mul, iterable):
    print(i, end = ' ')

Kush1101

from itertools import islice

l = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

for i in islice(l, 1, 9, 1):
    print(i, end =' ')
# OUTPUT
"""
2 3 4 5 6 7 8 9
"""

Kush1101

from itertools import filterfalse

iterable = [1, 3, 5, 7, 2, 4, 6, 9, 11]
predicate = lambda x: x%2==0

for i in filterfalse(predicate, iterable):
    print(i, end = ' ')

# OUTPUT
"""

Kush1101

from itertools import dropwhile

iterable = [1, 3, 5, 7, 2, 4, 6, 9, 11]
predicate = lambda x: x%2==1

for i in dropwhile(predicate, iterable):
    print(i, end = ' ')
# OUTPUT
"""
2 4 6 9 11

Kush1101

from itertools import cycle

count = 0
iterable = ["Python", "is", "awesome."]

generator = cycle(iterable)
for i in range(6):
    print(next(generator, end = ' ')
          
# OUTPUT