private void ensureCustomAttributesIsMutable() {
            if ((bitField0_ & 0x00000002) == 0) {
                customAttributes_ = new java.util.ArrayList<>(customAttributes_);
                bitField0_ |= 0x00000002;
            }
        }
<code>map&lt;int64, string&gt; question_id_to_answer = 1;</code>
turms-server-common/src/main/java/im/turms/server/common/access/client/dto/request/group/enrollment/CheckGroupJoinQuestionsAnswersRequest.java