The "Import-Export Wavefront OBJ format" addon seems to be disabled. You need to enable this in the preferences.
Python: RuntimeError: class MPFB_OT_create_human, function execute: incompatible return value , : 'CANCELED' not found in ('RUNNING_MODAL', 'CANCELLED', 'FINISHED', 'PASS_THROUGH', 'INTERFACE')
Any idea how to fix this..