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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 expand(self, ident):
        '''Return expanded set of labels from a connected component.

        The connected component is derived from ``ident``. ``ident``
        may be a ``content_id`` or a ``(content_id, subtopic_id)``.
        If ``ident`` identifies a subtopic, then expansion is done
        on a subtopic connected component (and expanded labels retain
        subtopic information).

        The labels returned by :meth:`LabelStore.connected_component`
        contains only the :class:`Label` stored in the
        :class:`LabelStore`, and does not include the labels you can
        infer from the connected component. This method returns both
        the data-backed labels and the inferred labels.

        Subtopic assignments of the expanded labels will be empty. The
        ``annotator_id`` will be an arbitrary ``annotator_id`` within
        the connected component.

        :param str content_id: content id
        :param value: coreferent value
        :type value: :class:`CorefValue`
        :rtype: ``list`` of :class:`Label`
        '''
        subtopic = ident_has_subtopic(normalize_ident(ident))
        labels = list(self.connected_component(ident))
        labels.extend(expand_labels(labels, subtopic=subtopic))
        return labels