def get_body(b2_world, index):
    """ get the body in a given position

    :param b2_world: an handler to a b2World object
    :type b2_world: b2World reference

    :param index: the index in the json list of joints 
    :type index: integer

    :return: the body in the given position
    :rtype: b2Body

    """
    return b2_world.bodies[index]