private com.google.protobuf.MapFieldBuilder<java.lang.String, im.turms.server.common.access.client.dto.model.common.ValueOrBuilder, im.turms.server.common.access.client.dto.model.common.Value, im.turms.server.common.access.client.dto.model.common.Value.Builder> internalGetMutableUserDefinedAttributes() {
            if (userDefinedAttributes_ == null) {
                userDefinedAttributes_ =
                        new com.google.protobuf.MapFieldBuilder<>(userDefinedAttributesConverter);
            }
            bitField0_ |= 0x00000040;
            onChanged();
            return userDefinedAttributes_;
        }
<code>optional int64 mute_end_date = 6;</code>

@return This builder for chaining.
turms-server-common/src/main/java/im/turms/server/common/access/client/dto/request/group/CreateGroupRequest.java