Remove item from list based on the next item in same list

Question

I just started learning python and here I have a sorted list of protein sequences (total 59,000 sequences) and some of them overlap. I have made a toy list here for example:

Answer 1

with open('demo.txt') as f:
    lines = f.readlines()

l_lines = len(lines)

n_lst = []

for i, line in enumerate(lines):
    line = line.strip()
    if i == l_lines - 1:
        if lines[-2] not in line:
            n_lst.append(line)
        break
    if line not in lines[i + 1]:
        n_lst.append(line)

print(n_lst)

Output

['ABCDEFGHIJKLMNO', 'CEST', 'DBTSFDEO', 'EOEUDNBNUW', 'EAEUDNBNUW', 'FGH']