code: @PublicEvolving
  	public <OUT> SingleOutputStreamOperator<OUT> process(
  			final BroadcastProcessFunction<IN1, IN2, OUT> function,
  			final TypeInformation<OUT> outTypeInfo) {
  
  		Preconditions.checkNotNull(function);
  		Preconditions.checkArgument(!(inputStream1 instanceof KeyedStream),
  				"A BroadcastProcessFunction can only be used on a non-keyed stream.");
  
  		TwoInputStreamOperator<IN1, IN2, OUT> operator =
  				new CoBroadcastWithNonKeyedOperator<>(clean(function), broadcastStateDescriptors);
  		return transform("Co-Process-Broadcast", outTypeInfo, operator);
  	}
docs: Assumes as inputs a {@link BroadcastStream} and a non-keyed {@link DataStream} and applies the given
  {@link BroadcastProcessFunction} on them, thereby creating a transformed output stream.
  
  @param function The {@link BroadcastProcessFunction} that is called for each element in the stream.
  @param outTypeInfo The type of the output elements.
  @param <OUT> The type of the output elements.
  @return The transformed {@link DataStream}.