xappend
=======

.. py:function:: t3toolbox.backend.common.xappend(S, x)

   .. code-block:: python

      def xappend(
              S: typ.Union[NDArray, typ.Sequence],  # array or sequence to append to
              x,                                     # slice (if S is an array) or element (if S is a sequence)
      ) -> typ.Union[NDArray, typ.Tuple]:            # S with x appended


   Append slice to array or element to sequence