Uniqueprefix

words = ['solve', 'geometri', 'solv', 'calcul', 'calculator']

result = []

wPrev = None
for w in sorted(set(words)):
    if not wPrev or (wPrev and not w.startswith(wPrev)):
        result.append(w)

    wPrev = w

print(result)

#### atau ###

words = list(set(words))
words2 = words[:]

for w in words:
    for w2 in words2:
        if w.startswith(w2) and (w != w2):
            words2.remove(w); break


result = words2

print(result)