The Gradle code base is essentially a large monolith, without strong internal boundaries.
This has a number of negative effects on productivity, including:

- Unclear ownership of code.
- Difficult to focus on one particular area.
- Unintended coupling between areas of the code, including tests.

## Decision

Organize the Gradle code base into a set of coarse-grained "architecture modules".

The [Hasher] interface type defines the contract between values of a
particular type and future hash-based data structures such as hash

{* ../../docs_src/cors/tutorial001_py310.py hl[2,6:11,13:19] *}


The default parameters used by the `CORSMiddleware` implementation are restrictive by default, so you'll need to explicitly enable particular origins, methods, or headers, in order for browsers to be permitted to use them in a Cross-Domain context.

The following arguments are supported:

 * Collection} and {@link Iterator} interfaces. The Iterator provided in method {@link #iterator()}
 * is not guaranteed to traverse the elements of the MonitorBasedPriorityBlockingQueue in
 * any particular order. If you need ordered traversal, consider using {@code
 * Arrays.sort(pq.toArray())}. Also, method {@code drainTo} can be used to remove some or
 * all elements in priority order and place them in another collection.

      /*
       * It's theoretically possible for Reference.reachabilityFence to exist under older VMs but
       * not work. (Under Android in particular, we really should check the API Level instead of
       * probing for methods....) But it's hard to imagine how reachabilityFence in particular could
       * exist but throw, so we propagate anything that's thrown, presumably an unchecked Exception
       * or Error.
       */

* A particular program while it is **running** on the operating system, using the CPU, and storing things in memory. This is also called a **process**.

### What is a Process { #what-is-a-process }

The word **process** is normally used in a more specific way, only referring to the thing that is running in the operating system (like in the last point above):

Avoid writing the so-called `PolyNull` or `ParametricNull` methods (where nullability of the result depends on the nullability of the type argument).

# Custom Request and APIRoute class { #custom-request-and-apiroute-class }

In some cases, you may want to override the logic used by the `Request` and `APIRoute` classes.

In particular, this may be a good alternative to logic in a middleware.

For example, if you want to read or manipulate the request body before it is processed by your application.

/// danger

This is an "advanced" feature.

 *       smallest sensible numbers of threads, collection sizes, etc needed to check basic
 *       conformance.
 *   <li>The test classes currently do not declare inclusion in any particular package to simplify
 *       things for people integrating them in TCK test suites.
 * </ul>
 */
@SuppressWarnings({
  // We call threadUnexpectedException, which does the right thing for errors.

When you are iterating over something, like a file-like object, and then you are doing `yield` for each item, you could also use `yield from` to yield each item directly and skip the `for` loop.

This is not particular to FastAPI, it's just Python, but it's a nice trick to know. 😎