DEPRECATED, use ``concat`` instead

    Parameters
    ----------
    arrays : list of `NDArray`
        Arrays to be concatenate. They must have identical shape except
        the first dimension. They also must have the same data type.
    axis : int
        The axis along which to concatenate.
    always_copy : bool
        Default `True`. When not `True`, if the arrays only contain one
        `NDArray`, that element will be returned directly, avoid copying.

    Returns
    -------
    NDArray
        An `NDArray` that lives on the same context as `arrays[0].context`.

def concatenate(arrays, axis=0, always_copy=True):
    """DEPRECATED, use ``concat`` instead

    Parameters
    ----------
    arrays : list of `NDArray`
        Arrays to be concatenate. They must have identical shape except
        the first dimension. They also must have the same data type.
    axis : int
        The axis along which to concatenate.
    always_copy : bool
        Default `True`. When not `True`, if the arrays only contain one
        `NDArray`, that element will be returned directly, avoid copying.

    Returns
    -------
    NDArray
        An `NDArray` that lives on the same context as `arrays[0].context`.
    """
    assert isinstance(arrays, list)
    assert len(arrays) > 0
    assert isinstance(arrays[0], NDArray)

    if not always_copy and len(arrays) == 1:
        return arrays[0]

    shape_axis = arrays[0].shape[axis]
    shape_rest1 = arrays[0].shape[0:axis]
    shape_rest2 = arrays[0].shape[axis+1:]
    dtype = arrays[0].dtype
    for arr in arrays[1:]:
        shape_axis += arr.shape[axis]
        assert shape_rest1 == arr.shape[0:axis]
        assert shape_rest2 == arr.shape[axis+1:]
        assert dtype == arr.dtype
    ret_shape = shape_rest1 + (shape_axis,) + shape_rest2
    ret = empty(ret_shape, ctx=arrays[0].context, dtype=dtype)

    idx = 0
    begin = [0 for _ in ret_shape]
    end = list(ret_shape)
    for arr in arrays:
        if axis == 0:
            ret[idx:idx+arr.shape[0]] = arr
        else:
            begin[axis] = idx
            end[axis] = idx+arr.shape[axis]
            # pylint: disable=no-member,protected-access
            _internal._crop_assign(ret, arr, out=ret,
                                   begin=tuple(begin),
                                   end=tuple(end))
            # pylint: enable=no-member,protected-access
        idx += arr.shape[axis]

    return ret