#Anim controls

bpy.ops.object.select_same_group(group="MyGroup")
nla_strips = []
for obj in bpy.context.selected_objects:
    if obj.animation_data is not None:
        action = obj.animation_data.action
        if action is not None:
            track = obj.animation_data.nla_tracks.new()
            track.strips.new(action.name, action.frame_range[1], action)
            obj.animation_data.action = None

            if obj.animation_data and obj.animation_data.nla_tracks:

                for track in obj.animation_data.nla_tracks:

                    for strip in track.strips:
                        nla_strips.append((strip,))
                        strip.frame_start = 60