I am trying to segment the list and then remove duplicates according to the given input values ? However I am missing something

Question

There are 2 inputs given

1. A string at N length.
2. An integer k that satisfies the condition: N % k = 0

For instance:

"AABCAAADA"

3

In this case I need to divide string into (9/3) 3 subparts and then I need to remove the duplicates .

explanation -> you can see the demonstration here.

I wrote a code that does the exact thing, however at the end of my output section I see "None". I couldn't figure out where did that come from..

Here is my code:

s = "AABCAAADA"
k = 3
def merge_the_tools(string, k):
    ls = segment(string,k)
    for l in ls:
        print(remove_repetitive(l))

def remove_repetitive(string):
    temp = list(dict.fromkeys(string))
    return "".join(temp)


def segment(string,k):
    ls = []
    segment_len = int(len(string) / k)
    x = 0
    for i in range(segment_len):
        ls.append(string[x:x+k])
        x += k
    return ls

print(merge_the_tools(s,k))

And this is my output:

AB
CA
AD
None

Answer 1

k = 3

new = [s[((x+1)*3)-3:(x+1)*3] for x in range(k)]

new = list(map(set, new))

print(new)

>>> ({'B', 'A'}, {'C', 'A'}, {'D', 'A'})

This line [((x+1)*3)-3:(x+1)*3] just gets the next three items and makes a list out of them and adds it to the overall list.

This line list(map(set, new)) just removes duplicates from each list.