Question: What weapon, designed by Aimo Lahti, was a descendant of the M-22 prototype and the KP/-26 production model?
Sentence (from "Suomi KP/-31"): The Suomi KP/-31 (Suomi-konepistooli or "Submachine-gun Finland", literally: "Machine-pistol Finland") was a submachine gun (SMG) of Finnish design used during World War II.
Relevant evidence: Yes