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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 get_pmids(self):
 """Get list of all PMIDs associated with edges in the network."""

        pmids = []
        for ea in self._edge_attributes.values():
            edge_pmids = ea.get('pmids')
            if edge_pmids:
                pmids += edge_pmids
        return list(set(pmids))