I’m a beginner who’d like to return strings in pairs of characters. If the input to the function is odd then the last pair it to include an _.

Example: solution("asdfadb") should return ['as', 'df', 'ad', 'b_']

My code however, returns: ['a', 's']['d', 'f']['a', 'd']['b', '_']

I’ve tried multiple ways and cannot get it to return the correctly formatted result:

def solution(s):
    if len(s)%2 != 0:
        s = "".join((s, "_"))
    s = list(s)
    s = [ s[i:i+2] for i in range(0 , len(s) , 2) ]
    s = ''.join(str(pair) for pair in s )
    print(s)

solution("asdfadb")
['a', 's']['d', 'f']['a', 'd']['b', '_']

>Solution :

You had a small confusion in the last list comprehension, try this (see my comment):

def solution(s):
    if len(s)%2 != 0:
        s = "".join((s, "_"))
    s = list(s)
    s = [ s[i:i+2] for i in range(0 , len(s) , 2) ]
    s = [''.join(pair) for pair in s] # For each sublist (aka pair) - do join.
    print(s)

Output:

['as', 'df', 'ad', 'b_']