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The `CustomOutputParser` needs to throw `OutputParserException` when it
fails to parse the response from the agent, so that the executor can
[catch it and
retry](be9371ca8f/langchain/agents/agent.py (L767))
when `handle_parsing_errors=True`.
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#### Who can review?
Tag maintainers/contributors who might be interested: @hwchase17
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#### Description
- Removed two backticks surrounding the phrase "chat messages as"
- This phrase stood out among other formatted words/phrases such as
`prompt`, `role`, `PromptTemplate`, etc., which all seem to have a clear
function.
- `chat messages as`, formatted as such, confused me while reading,
leading me to believe the backticks were misplaced.
#### Who can review?
@hwchase17
<!-- For a quicker response, figure out the right person to tag with @
@hwchase17 - project lead
Tracing / Callbacks
- @agola11
Async
- @agola11
DataLoaders
- @eyurtsev
Models
- @hwchase17
- @agola11
Agents / Tools / Toolkits
- @hwchase17
VectorStores / Retrievers / Memory
- @dev2049
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