* `ge`: `g`reater than or `e`qual
* `lt`: `l`ess `t`han
* `le`: `l`ess than or `e`qual

/// info

`Query`, `Path`, and other classes you will see later are subclasses of a common `Param` class.

All of them share the same parameters for additional validation and metadata you have seen.

///

/// note | Technical Details

When you import `Query`, `Path` and others from `fastapi`, they are actually functions.

# Async Tests { #async-tests }

You have already seen how to test your **FastAPI** applications using the provided `TestClient`. Up to now, you have only seen how to write synchronous tests, without using `async` functions.

# Extra Data Types { #extra-data-types }

Up to now, you have been using common data types, like:

* `int`
* `float`
* `str`
* `bool`

But you can also use more complex data types.

And you will still have the same features as seen up to now:

* Great editor support.
* Data conversion from incoming requests.
* Data conversion for response data.
* Data validation.
* Automatic annotation and documentation.

	for _, c := range s {
		if c < 0x80 && c != 0x00 {
			b = append(b, byte(c))
		}
	}
	return string(b)
}

type parser struct {
	err error // Last error seen
}

type formatter struct {
	err error // Last error seen
}

// parseString parses bytes as a NUL-terminated C-style string.
// If a NUL byte is not found then the whole slice is returned as a string.
func (*parser) parseString(b []byte) string {

# Custom Response - HTML, Stream, File, others { #custom-response-html-stream-file-others }

By default, **FastAPI** will return JSON responses.

You can override it by returning a `Response` directly as seen in [Return a Response directly](response-directly.md).

containing a query.

 - CallStart
 - **CacheHit**
 - CallEnd

### Cache Miss

Under a cache miss the normal request events are seen but an additional event shows the presence of the cache.
Cache Miss will be typical if the item has not been read from the network, is uncacheable, or is past it's
lifetime based on Response cache headers.

 - CallStart
 - **CacheMiss**
 - ProxySelectStart

# Body - Multiple Parameters { #body-multiple-parameters }

Now that we have seen how to use `Path` and `Query`, let's see more advanced uses of request body declarations.

## Mix `Path`, `Query` and body parameters { #mix-path-query-and-body-parameters }

First, of course, you can mix `Path`, `Query` and request body parameter declarations freely and **FastAPI** will know what to do.

    // Don't copy this into your own test!
    // Use e.g. awaitClear or await(CountDownLatch) instead.
    GcFinalization.awaitFullGc();

    // Attempt to help with some flakiness that we've seen: b/387521512.
    GcFinalization.awaitFullGc();

    assertEquals(0, finalizerRan.getCount());
    assertThat(ref.get()).isNull();
  }

        return;
      }
      // Otherwise, it's the first time seeing this lock relationship. Look for
      // a path from the acquiredLock to this.
      Set<LockGraphNode> seen = Sets.newIdentityHashSet();
      ExampleStackTrace path = acquiredLock.findPathTo(this, seen);

      if (path == null) {
        // this can be safely acquired after the acquiredLock.
        //

   * Sets {@code table[index]} to {@code entry}, where {@code table} is actually a {@code byte[]},
   * {@code short[]}, or {@code int[]}. The value of {@code entry} should fit in the size of the
   * assigned array element, when seen as an unsigned value. So if {@code table} is a {@code byte[]}
   * then we should have {@code 0 ≤ entry ≤ 255}, and if {@code table} is a {@code short[]} then we