## Conclusion

With this you should have a basic understanding of what **environment variables** are and how to use them in Python.

You can also read more about them in the <a href="https://en.wikipedia.org/wiki/Environment_variable" class="external-link" target="_blank">Wikipedia for Environment Variable</a>.

## Client and SDK Generators - Sponsor

There are also some **company-backed** Client and SDK generators based on OpenAPI (FastAPI), in some cases they can offer you **additional features** on top of high-quality generated SDKs/clients.

 *       when using Executors.
 * </ol>
 *
 * <p><b>Other notes</b>
 *
 * <ul>
 *   <li>Usually, there is one testcase method per JSR166 method covering "normal" operation, and
 *       then as many exception-testing methods as there are exceptions the method can throw.
 *       Sometimes there are multiple tests per JSR166 method when the different "normal" behaviors

* Then it returns the **response**.

/// note | "Technical Details"

If you have dependencies with `yield`, the exit code will run *after* the middleware.

If there were any background tasks (documented later), they will run *after* all the middleware.

///

## Create a middleware

To create a middleware you use the decorator `@app.middleware("http")` on top of a function.

        #### Utility: compare with alternatives


        There is always *some* alternative to adding a new feature to Guava, even if it's just
        forking Guava yourself.


        We want to see that new features have some significant advantage over the alternatives.
        These advantages can take
        [many forms](https://github.com/google/guava/wiki/PhilosophyExplained#utility), but taking

Since HTTP requests frequently happen in parallel, connection pooling must be thread-safe.

3. The EGLDisplay and EGLConfig types from the EGL API.

These types are uintptr on the Go side because they would otherwise
confuse the Go garbage collector; they are sometimes not really
pointers but data structures encoded in a pointer type. All operations
on these types must happen in C. The proper constant to initialize an
empty such reference is 0, not nil.

These special cases were introduced in Go 1.10. For auto-updating code

* `fixedquery`: has the exact value `fixedquery`.
* `$`: ends there, doesn't have any more characters after `fixedquery`.

If you feel lost with all these **"regular expression"** ideas, don't worry. They are a hard topic for many people. You can still do a lot of stuff without needing regular expressions yet.

But whenever you need them and go and learn them, know that you can already use them directly in **FastAPI**.

   * least values, the first of those is returned.
   *
   * <p><b>Java 8+ users:</b> If {@code iterable} is a {@link Collection}, use {@code
   * Collections.min(collection, thisComparator)} instead. Otherwise, use {@code
   * Streams.stream(iterable).min(thisComparator).get()} instead. Note that these alternatives do

    * This is especially useful if you run `await myfile.read()` once and then need to read the contents again.
* `close()`: Closes the file.

As all these methods are `async` methods, you need to "await" them.

For example, inside of an `async` *path operation function* you can get the contents with:

```Python
contents = await myfile.read()
```