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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 log_entries(self, time_zone='UTC', is_overview=False, include=None, fetch_all=True):
 """Query for log entries on an incident instance."""

        endpoint = '/'.join((self.endpoint, self.id, 'log_entries'))

        query_params = {
            'time_zone': time_zone,
            'is_overview': json.dumps(is_overview),
        }

        if include:
            query_params['include'] = include

        result = self.logEntryFactory.find(
            endpoint=endpoint,
            api_key=self.api_key,
            fetch_all=fetch_all,
            **query_params
        )

        return result