For this simple example, we are going to just be completely insecure and return the same `username` as the token.

!!! tip
    In the next chapter, you will see a real secure implementation, with password hashing and <abbr title="JSON Web Tokens">JWT</abbr> tokens.

    But for now, let's focus on the specific details we need.

=== "Python 3.10+"

    ```Python hl_lines="87"

  fun networkInterceptorThrowsRuntimeExceptionSynchronous() {
    interceptorThrowsRuntimeExceptionSynchronous(true)
  }

  /**
   * When an interceptor throws an unexpected exception, synchronous callers can catch it and deal
   * with it.
   */
  private fun interceptorThrowsRuntimeExceptionSynchronous(network: Boolean) {
    addInterceptor(network) { chain: Interceptor.Chain? -> throw RuntimeException("boom!") }
    val request =

Copyright (C) 2016 Daniel Dreibrodt

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is

But still, the final experience is not the best. 😞

---

This would be the parallel equivalent story for burgers. 🍔

For a more "real life" example of this, imagine a bank.

Up to recently, most of the banks had multiple cashiers 👨‍💼👨‍💼👨‍💼👨‍💼 and a big line 🕙🕙🕙🕙🕙🕙🕙🕙.

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    FastAPI framework, yüksek performanslı, öğrenmesi oldukça kolay, kodlaması hızlı, kullanıma hazır
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    Готовий до продакшину, високопродуктивний, простий у вивченні та швидкий для написання коду фреймворк
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!!! info
    In this example we use invented custom headers `X-Key` and `X-Token`.

    But in real cases, when implementing security, you would get more benefits from using the integrated [Security utilities (the next chapter)](../security/index.md){.internal-link target=_blank}.

## Dependencies errors and return values

  // For example: the master will return an internal IP CIDR only, if the client reaches the server using an internal IP.
  // Server looks at X-Forwarded-For header or X-Real-Ip header or request.RemoteAddr (in that order) to get the client IP.
  // +optional
  repeated ServerAddressByClientCIDR serverAddressByClientCIDRs = 4;
}

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    Framework FastAPI, haute performance, facile à apprendre, rapide à coder, prêt pour la production
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    FastAPI framework, high performance, easy to learn, fast to code, ready for production
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