![Swagger UI](https://fastapi.tiangolo.com/img/index/index-03-swagger-02.png)

* Klik op de knop "Try it out", hiermee kan je de parameters invullen en direct met de API interacteren:

![Swagger UI interaction](https://fastapi.tiangolo.com/img/index/index-04-swagger-03.png)

{!> ../../docs_src/dependencies/tutorial001.py!}
```

////

But then we get a `dict` in the parameter `commons` of the *path operation function*.

And we know that editors can't provide a lot of support (like completion) for `dict`s, because they can't know their keys and value types.

We can do better...

## What makes a dependency

Up to now you have seen dependencies declared as functions.

// just nice to know that it compiles.
void* create(TF_OpKernelConstruction* ctx) {
  TF_DataType type;
  TF_Status* s = TF_NewStatus();
  TF_OpKernelConstruction_GetAttrType(ctx, "foobar", &type, s);
  TF_DeleteStatus(s);
  return NULL;
}

// A compute function. This will never actually get called in this test, it's
// just nice to know that it compiles.

     *   <li>If this field's value is some other thread object, we know that it's not our thread.
     *   <li>If this field's value == null because it originally belonged to another thread and that
     *       thread cleared it, we still know that it's not associated with our thread
     *   <li>If this field's value == null because it was associated with our thread and was
     *       cleared, we know that we're not executing inline any more
     * </ul>

     *   <li>If this field's value is some other thread object, we know that it's not our thread.
     *   <li>If this field's value == null because it originally belonged to another thread and that
     *       thread cleared it, we still know that it's not associated with our thread
     *   <li>If this field's value == null because it was associated with our thread and was
     *       cleared, we know that we're not executing inline any more
     * </ul>

    if (mapEntryBelowToTruncate != null) {
      // we know ( [
      RangeMapEntry<K, V> rangeMapEntry = mapEntryBelowToTruncate.getValue();
      if (rangeMapEntry.getUpperBound().compareTo(rangeToRemove.lowerBound) > 0) {
        // we know ( [ )
        if (rangeMapEntry.getUpperBound().compareTo(rangeToRemove.upperBound) > 0) {
          // we know ( [ ] ), so insert the range ] ) back into the map --

    assertThat(partMno.body.readUtf8()).isEqualTo("mnop")

    assertThat(parts.nextPart()).isNull()
  }

  @Test fun `cannot read part after calling nextPart`() {
    val multipart =
      """
      |--simple boundary
      |
      |abcd
      |efgh
      |ijkl
      |--simple boundary
      |
      |mnop
      |--simple boundary--
      """.trimMargin()

```

////

/// info

Notice that we are only declaring one dependency in the *path operation function*, the `query_or_cookie_extractor`.

But **FastAPI** will know that it has to solve `query_extractor` first, to pass the results of that to `query_or_cookie_extractor` while calling it.

///

```mermaid
graph TB

query_extractor(["query_extractor"])

    if (mapEntryBelowToTruncate != null) {
      // we know ( [
      RangeMapEntry<K, V> rangeMapEntry = mapEntryBelowToTruncate.getValue();
      if (rangeMapEntry.getUpperBound().compareTo(rangeToRemove.lowerBound) > 0) {
        // we know ( [ )
        if (rangeMapEntry.getUpperBound().compareTo(rangeToRemove.upperBound) > 0) {
          // we know ( [ ] ), so insert the range ] ) back into the map --

How to contribute
=================

Thank you so much for wanting to contribute to Guava! Here are a few important
things you should know about contributing:

1.  API changes require discussion, use cases, etc. Code comes later.
2.  Pull requests are great for small fixes for bugs, documentation, etc.
3.  Pull requests are not merged directly into the master branch.
4.  Code contributions require signing a Google CLA.

API changes
-----------