```Python hl_lines="6-7"
{!../../docs_src/query_params/tutorial005.py!}
```

Here the query parameter `needy` is a required query parameter of type `str`.

If you open in your browser a URL like:

```
http://127.0.0.1:8000/items/foo-item
```

...without adding the required parameter `needy`, you will see an error like:

```JSON
{
  "detail": [
    {

    public boolean equals(@Nullable Object o) {
      if (!(o instanceof ValidTestObject)) {
        return false;
      }
      ValidTestObject other = (ValidTestObject) o;
      if (aspect1 != other.aspect1) {
        return false;
      }
      if (aspect2 != other.aspect2) {
        return false;
      }
      return true;
    }

    @Override
    public int hashCode() {
      int result = 17;

class Relay private constructor(
  /**
   * Read/write persistence of the upstream source and its metadata. Its layout is as follows:
   *
   *  * 16 bytes: either `OkHttp cache v1\n` if the persisted file is complete. This is another
   *    sequence of bytes if the file is incomplete and should not be used.
   *  * 8 bytes: *n*: upstream data size
   *  * 8 bytes: *m*: metadata size
   *  * *n* bytes: upstream data
   *  * *m* bytes: metadata
   *

///

## Data <abbr title="also known as: serialization, parsing, marshalling">conversion</abbr>

If you run this example and open your browser at <a href="http://127.0.0.1:8000/items/3" class="external-link" target="_blank">http://127.0.0.1:8000/items/3</a>, you will see a response of:

```JSON
{"item_id":3}
```

/// check

  - [Changelog since v1.5.7](#changelog-since-v157)
    - [Other notable changes](#other-notable-changes)
- [v1.5.7](#v157)
  - [Downloads for v1.5.7](#downloads-for-v157)
    - [Client Binaries](#client-binaries-1)
    - [Server Binaries](#server-binaries-1)
    - [Node Binaries](#node-binaries-1)
  - [Changelog since v1.5.6](#changelog-since-v156)
    - [Other notable changes](#other-notable-changes-1)
- [v1.5.6](#v156)

    - [Other notable changes](#other-notable-changes-6)
- [v1.4.3](#v143)
  - [Downloads](#downloads)
  - [Changelog since v1.4.2-beta.1](#changelog-since-v142-beta1)
    - [Other notable changes](#other-notable-changes-7)
- [v1.4.2](#v142)
  - [Downloads](#downloads-1)
  - [Changelog since v1.4.2-beta.1](#changelog-since-v142-beta1-1)
    - [Other notable changes](#other-notable-changes-8)

      return this;
    }

    @CanIgnoreReturnValue
    Builder<K, V> combine(Builder<K, V> other) {
      checkNotNull(other);
      ensureCapacity(this.size + other.size);
      arraycopy(other.entries, 0, this.entries, this.size, other.size);
      this.size += other.size;
      return this;
    }

    private ImmutableMap<K, V> build(boolean throwIfDuplicateKeys) {
      /*

    /**
     * This is really just for {@link jcifs.netbios.UniAddress}. It does
     * not throw an {@link java.net.UnknownHostException} because this
     * is queried frequently and exceptions would be rather costly to
     * throw on a regular basis here.
     * 
     * @param host
     * @param tc
     * @return resolved name, null if not found
     */

## FastAPI App with Tags

In many cases your FastAPI app will be bigger, and you will probably use tags to separate different groups of *path operations*.

For example, you could have a section for **items** and another section for **users**, and they could be separated by tags:

//// tab | Python 3.9+

```Python hl_lines="21  26  34"
{!> ../../docs_src/generate_clients/tutorial002_py39.py!}
```

////

      return true;
    }
    if (!(obj instanceof Network)) {
      return false;
    }
    Network<?, ?> other = (Network<?, ?>) obj;

    return isDirected() == other.isDirected()
        && nodes().equals(other.nodes())
        && edgeIncidentNodesMap(this).equals(edgeIncidentNodesMap(other));
  }

  @Override
  public final int hashCode() {
    return edgeIncidentNodesMap(this).hashCode();
  }