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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(self):
 """Object to index ``self`` along axes. Examples -------- Indexing with integers or slices: uniform_partition(0.0, 1.0, 3) uniform_partition(1.0, 3.0, 5) uniform_partition(2.0, 5.0, 6) True uniform_partition([ 1., 2.], [ 3., 5.], (5, 6)) Lists can be used to stack subpartitions arbitrarily: uniform_partition([ 0., 2., 0.], [ 1., 5., 1.], (3, 6, 3)) """

        partition = self

        class RectPartitionByAxis(object):

            """Helper class for accessing `RectPartition` by axis."""

            def __getitem__(self, indices):
                """Return ``self[indices]``."""
                try:
                    iter(indices)
                except TypeError:
                    # Slice or integer
                    slc = np.zeros(partition.ndim, dtype=object)
                    slc[indices] = slice(None)
                    squeeze_axes = np.where(slc == 0)[0]
                    newpart = partition[tuple(slc)].squeeze(squeeze_axes)
                else:
                    # Sequence, stack together from single-integer indexing
                    indices = [int(i) for i in indices]
                    byaxis = partition.byaxis
                    parts = [byaxis[i] for i in indices]
                    if not parts:
                        newpart = uniform_partition([], [], ())
                    else:
                        newpart = parts[0].append(*(parts[1:]))

                return newpart

            def __repr__(self):
                """Return ``repr(self)``.

                Examples
                --------
                >>> p = odl.uniform_partition(0, 1, 5)
                >>> p.byaxis
                uniform_partition(0, 1, 5).byaxis
                """
                return '{!r}.byaxis'.format(partition)

        return RectPartitionByAxis()