uniloadMultipart

suspend fun <ERROR CLASS>.uniloadMultipart(onFormItem: (<ERROR CLASS>) -> Unit = {}, onCustomFileItem: (<ERROR CLASS>) -> Unit = {}, onBinaryContent: (<ERROR CLASS>) -> Unit = {}): <ERROR CLASS>
suspend fun <T> <ERROR CLASS>.uniloadMultipart(deserializer: DeserializationStrategy<T>, onFormItem: (<ERROR CLASS>) -> Unit = {}, onCustomFileItem: (<ERROR CLASS>) -> Unit = {}, onBinaryContent: (<ERROR CLASS>) -> Unit = {}): Pair<<ERROR CLASS>, T>