Yes, you can disable drawing of constraints by setting the flags property on the SpaceDebugDrawOptions object to only include shapes, or if you prefer include both shapes and collisions: http://www.pymunk.org/en/latest/pymunk.html#pymunk.SpaceDebugDrawOptions.flags
in this way to draw only shapes
options = pymunk.pygame_util.DrawOptions(screen)
options.flags = pymunk.SpaceDebugDrawOptions.DRAW_SHAPES
or like this to draw both shapes and collisions
options = pymunk.pygame_util.DrawOptions(screen)
options.flags = pymunk.SpaceDebugDrawOptions.DRAW_SHAPES | pymunk.SpaceDebugDrawOptions.DRAW_COLLISION_POINTS