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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 count(self, query):
 """ Returns number of matching entries :type query str :rtype: int """

        body = {
            "query": {
                "bool": {
                    "must": [{
                        "query_string": {
                            "query": query,
                        }
                    }]
                }
            }
        }

        body['query']['bool']['must'].append(self._get_timestamp_filer())

        return self._es.count(index=self._index, body=body).get('count')