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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 read_audit_log(self, symbol=None):
 """ Reads the audit log Parameters symbol: str optionally only retrieve specific symbol's audit information Returns ------- list of dicts """

        if symbol:
            return [x for x in self._audit.find({'symbol': symbol}, {'_id': False})]
        return [x for x in self._audit.find({}, {'_id': False})]