ufv_stack
=========

.. py:function:: t3toolbox.backend.ufv_operations.ufv_stack(xx, n_supercores)

   .. code-block:: python

      def ufv_stack(
              xx,                       # nested tuple (shaped like stack_shape) of unstacked bv .data leaves
              n_supercores: int,        # 4 (frame) or 2 (variations)
      ) -> typ.Tuple:                   # one stacked bv .data tuple (*supercores, shape, masks)


   Stack an array-like tree of bv ``.data`` leaves into one (the WHOLE stack at axes ``1 ..``). Inverse
   of :py:func:`ufv_unstack`; thin wrapper over :py:func:`ufv_stack_axes` with ``axes_start = 1``.