def extend_instance(obj, cls):
    """ Apply mixins to a class instance after creation
    Parameters
    ----------
    obj : object (not class!) targeted for interface extension
          Interface carries throughout its lifetime.
    cls : class (not object!) to dynamically mixin

    Returns
    -------
    None

    Credits
    -------
    https://stackoverflow.com/a/31075641
    """
    base_cls = obj.__class__
    base_cls_name = obj.__class__.__name__
    obj.__class__ = type(base_cls_name, (cls, base_cls), {})
