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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_documents(self):
 """Populate sentences attribute with a dict keyed by document id."""

        documents = self.tree.execute("$.documents")
        for doc in documents:
            sentences = {s['@id']: s['text'] for s in doc.get('sentences', [])}
            self.document_dict[doc['@id']] = {'sentences': sentences,
                                              'location': doc['location']}