# Resolve error in StructuredOutputParser docs
Documentation for `StructuredOutputParser` currently not reproducible,
that is, `output_parser.parse(output)` raises an error because the LLM
returns a response with an invalid format
```python
_input = prompt.format_prompt(question="what's the capital of france")
output = model(_input.to_string())
output
# ?
#
# ```json
# {
# "answer": "Paris",
# "source": "https://www.worldatlas.com/articles/what-is-the-capital-of-france.html"
# }
# ```
```
Was fixed by adding a question mark to the prompt