public static <M> OutputOperatorSpec<M> createSendToOperatorSpec(OutputStreamImpl<M> outputStream, String opId) {
    return new OutputOperatorSpec<>(outputStream, opId);
  }
Creates a {@link OutputOperatorSpec} for the sendTo operator.

@param outputStream  the {@link OutputStreamImpl} to send messages to
@param opId  the unique ID of the operator
@param <M> the type of message in the {@link OutputStreamImpl}
@return  the {@link OutputOperatorSpec} for the sendTo operator
samza-core/src/main/java/org/apache/samza/operators/spec/OperatorSpecs.java