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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 index_within_subset(self, indexable, subset_request, sort_indices=False):
 """Index an indexable object within the context of this subset. Parameters indexable : indexable object The object to index through. subset_request : :class:`list` or :class:`slice` List of positive integer indices or slice that constitutes the request *within the context of this subset*. This request will be translated to a request on the indexable object. sort_indices : bool, optional If the request is a list of indices, indexes in sorted order and reshuffles the result in the original order. Defaults to `False`. """

        # Translate the request within the context of this subset to a
        # request to the indexable object
        if isinstance(subset_request, numbers.Integral):
            request, = self[[subset_request]]
        else:
            request = self[subset_request]
        # Integer or slice requests can be processed directly.
        if isinstance(request, numbers.Integral) or hasattr(request, 'step'):
            return indexable[request]
        # If requested, we do fancy indexing in sorted order and reshuffle the
        # result back in the original order.
        if sort_indices:
            return self.sorted_fancy_indexing(indexable, request)
        # If the indexable supports fancy indexing (numpy array, HDF5 dataset),
        # the request can be processed directly.
        if isinstance(indexable, (numpy.ndarray, h5py.Dataset)):
            return indexable[request]
        # Anything else (e.g. lists) isn't considered to support fancy
        # indexing, so Subset does it manually.
        return iterable_fancy_indexing(indexable, request)