t3_from_tensor_train
====================

.. py:function:: t3toolbox.backend.t3_conversions.t3_from_tensor_train(tt_cores)

   .. code-block:: python

      def t3_from_tensor_train(
              tt_cores: typ.Sequence[NDArray],  # len=d, elm_shape=stack_shape+(rLi,Ni,rR(i+1))
      ) -> typ.Tuple[
          typ.Tuple[NDArray, ...],  # tucker_cores. len=d, identity bases, elm_shape=stack_shape+(Ni,Ni)
          typ.Tuple[NDArray, ...],  # tt_cores.     len=d, elm_shape=stack_shape+(rLi,Ni,rR(i+1))
      ]:


   Convert tensor train into Tucker tensor train by using identity matrices for Tucker bases.