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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def byaxis_out(self):
 """Object to index along output dimensions. This is only valid for non-trivial `out_shape`. Examples -------- Indexing with integers or slices: FunctionSpace(IntervalProd(0.0, 1.0), out_dtype=('float64', (2,))) FunctionSpace(IntervalProd(0.0, 1.0), out_dtype=('float64', (3,))) FunctionSpace(IntervalProd(0.0, 1.0), out_dtype=('float64', (3, 4))) Lists can be used to stack spaces arbitrarily: FunctionSpace(IntervalProd(0.0, 1.0), out_dtype=('float64', (4, 3, 4))) """

        space = self

        class FspaceByaxisOut(object):

            """Helper class for indexing by output axes."""

            def __getitem__(self, indices):
                """Return ``self[indices]``.

                Parameters
                ----------
                indices : index expression
                    Object used to index the output components.

                Returns
                -------
                space : `FunctionSpace`
                    The resulting space with same domain and scalar output
                    data type, but indexed output components.

                Raises
                ------
                IndexError
                    If this is a space of scalar-valued functions.
                """
                try:
                    iter(indices)
                except TypeError:
                    newshape = space.out_shape[indices]
                else:
                    newshape = tuple(space.out_shape[int(i)] for i in indices)

                dtype = (space.scalar_out_dtype, newshape)
                return FunctionSpace(space.domain, out_dtype=dtype)

            def __repr__(self):
                """Return ``repr(self)``."""
                return repr(space) + '.byaxis_out'

        return FspaceByaxisOut()