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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 _extract_core_semantics(self, docs):
 """ Extracts core semantics for a list of documents, returning them along with a list of all the concepts represented. """

        all_concepts = []
        doc_core_sems = []
        for doc in docs:
            core_sems = self._process_doc(doc)
            doc_core_sems.append(core_sems)
            all_concepts += [con for con, weight in core_sems]
        return doc_core_sems, list(set(all_concepts))