test.py

import lzma

with lzma.open('test.7z', 'w') as lf:
    lf.write(b'123\n'*1000)

with lzma.open('test.7z', 'r') as lf:
    arr = list(lf)

print(len(arr))
print(set(arr))
print(arr[0])
print(arr[0].decode('utf-8'))