<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
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<USER_TASK:>
Description:
 def get_comments_by_query(self, comment_query):
 """Gets a list of comments matching the given search. arg: comment_query (osid.commenting.CommentQuery):
 the search query array return: (osid.commenting.CommentList) - the returned ``CommentList`` raise: NullArgument - ``comment_query`` is ``null`` raise: OperationFailed - unable to complete request raise: PermissionDenied - authorization failure raise: Unsupported - ``comment_query`` is not of this service *compliance: mandatory -- This method must be implemented.* """

        # Implemented from template for
        # osid.resource.ResourceQuerySession.get_resources_by_query
        and_list = list()
        or_list = list()
        for term in comment_query._query_terms:
            if '$in' in comment_query._query_terms[term] and '$nin' in comment_query._query_terms[term]:
                and_list.append(
                    {'$or': [{term: {'$in': comment_query._query_terms[term]['$in']}},
                             {term: {'$nin': comment_query._query_terms[term]['$nin']}}]})
            else:
                and_list.append({term: comment_query._query_terms[term]})
        for term in comment_query._keyword_terms:
            or_list.append({term: comment_query._keyword_terms[term]})
        if or_list:
            and_list.append({'$or': or_list})
        view_filter = self._view_filter()
        if view_filter:
            and_list.append(view_filter)
        if and_list:
            query_terms = {'$and': and_list}
            collection = JSONClientValidated('commenting',
                                             collection='Comment',
                                             runtime=self._runtime)
            result = collection.find(query_terms).sort('_id', DESCENDING)
        else:
            result = []
        return objects.CommentList(result, runtime=self._runtime, proxy=self._proxy)