* was run [asynchronously][Call.enqueue] or [synchronously][Call.execute]. Asynchronous calls
   * become idle after the [onResponse][Callback.onResponse] or [onFailure][Callback.onFailure]
   * callback has returned. Synchronous calls become idle once [execute()][Call.execute] returns.
   * This means that if you are doing synchronous calls the network layer will not truly be idle

  ) {
    // Do nothing.
  }

  override fun noNewExchanges() {
    // Do nothing.
  }

  override fun cancel() {
    canceled = true
    // Close the raw socket so we don't end up doing synchronous I/O.
    rawSocket?.closeQuietly()
  }

  override fun retry(): RoutePlanner.Plan {
    return ConnectPlan(
      taskRunner = taskRunner,
      connectionPool = connectionPool,

		// whether to replicate as the target could be temporarily down
		opts.TargetArn = tgtArn
		replicate := cfg.Replicate(opts)
		var synchronous bool
		if tgt != nil {
			synchronous = tgt.replicateSync
		}
		dsc.Set(newReplicateTargetDecision(tgtArn, replicate, synchronous))
	}
	return dsc
}

// Standard headers that needs to be extracted from User metadata.
var standardHeaders = []string{

import okio.buffer
import okio.sink
import okio.source

/**
 * A socket connection to a remote peer. A connection hosts streams which can send and receive
 * data.
 *
 * Many methods in this API are **synchronous:** the call is completed before the method returns.
 * This is typical for Java but atypical for HTTP/2. This is motivated by exception transparency:

## Technical Details

Modern versions of Python have support for **"asynchronous code"** using something called **"coroutines"**, with **`async` and `await`** syntax.

Let's see that phrase by parts in the sections below:

* **Asynchronous Code**
* **`async` and `await`**
* **Coroutines**

## Asynchronous Code

and the [go command documentation](/cmd/go#hdr-Build_and_test_caching).

### Go 1.23

Go 1.23 changed the channels created by package time to be unbuffered
(synchronous), which makes correct use of the [`Timer.Stop`](/pkg/time/#Timer.Stop)
and [`Timer.Reset`](/pkg/time/#Timer.Reset) method results much easier.
The [`asynctimerchan` setting](/pkg/time/#NewTimer) disables this change.

      override fun cancel() {
        exchange.cancel()
      }
    }
  }

  override fun route(): Route = route

  override fun cancel() {
    // Close the raw socket so we don't end up doing synchronous I/O.
    rawSocket?.closeQuietly()
  }

  override fun socket(): Socket = socket!!

  /** Returns true if this connection is ready to host new streams. */

It has an interesting, uncommon feature: using the same framework, it's possible to create APIs and also CLIs.

As it is based on the previous standard for synchronous Python web frameworks (WSGI), it can't handle Websockets and other things, although it still has high performance too.

!!! info

When Go 1.23 builds older programs, the old behaviors remain in effect.
The new [GODEBUG setting](/doc/godebug) [`asynctimerchan=1`](/pkg/time/#NewTimer)
can be used to revert back to asynchronous channel behaviors

```Python hl_lines="1"
async def get_burgers(number: int):
    # Do some asynchronous stuff to create the burgers
    return burgers
```

...en vez de `def`:

```Python hl_lines="2"
# This is not asynchronous
def get_sequential_burgers(number: int):
    # Do some sequential stuff to create the burgers
    return burgers
```