Python: Descompactar arquivos em formato 7z

 Utilizando o sistema operacional:

import os
os.system( '7z x archive.7z -oPath/to/Name' )

Com pacote py7zr

import py7zr
with py7zr.SevenZipFile('sample.7z', mode='r') as z:
    z.extractall()

Com pacote pyunpack

from pyunpack import Archive
Archive('data.7z').extractall("<output path>")