My code:

def merge_the_tools(string, k): subs = [] word = ''

for i in range(1,len(string) + 1):
    if string[i-1] not in word:
        word += string[i-1]
    if i % k == 0:
        subs.append(word)
        word = ''

for j in range(0, len(subs)):
    print(subs[j])