* And it could also have a declaration of the response it should return, e.g. `response_model=InvoiceEventReceived`.

```Python hl_lines="16-18  21-22  28-32"
{!../../../docs_src/openapi_callbacks/tutorial001.py!}
```

There are 2 main differences from a normal *path operation*:

- login: krishnardt
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- login: panla
  count: 32
  avatarUrl: https://avatars.githubusercontent.com/u/41326348?u=ba2fda6b30110411ecbf406d187907e2b420ac19&v=4
  url: https://github.com/panla
- login: prostomarkeloff
  count: 28