Assigning additional values to an input
While the RunnableLambda
function returns a single value, you will also need to preserve the current state. RunnablePassthrough
does this by appending new keys to a dictionary holding the user input, so the inputs and results from RunnableLambda
can be stored alongside one another.
Complete the code to add an additional output
key to the chain's input.
This exercise is part of the course
Graph RAG with LangChain and Neo4j
Exercise instructions
- Use the correct runnable class to append an
output
key to the chain's input. - Extract the correct key from the input to multiply by
2
to complete thelambda
function.
Hands-on interactive exercise
Have a go at this exercise by completing this sample code.
# Add an output key to the chain
chain = RunnablePassthrough.____(
# Multiply the input by 2
output=lambda x: x[____] * 2
)
output = chain.invoke({"input": 2})
print(output)