* データ変換
* データの検証
* 自動文書化

## 特殊な型とバリデーション

`str`や`int`、`float`のような通常の単数型の他にも、`str`を継承したより複雑な単数型を使うこともできます。

すべてのオプションをみるには、<a href="https://docs.pydantic.dev/latest/concepts/types/" class="external-link" target="_blank">Pydanticのエキゾチック な型</a>のドキュメントを確認してください。次の章でいくつかの例をみることができます。

例えば、`Image`モデルのように`url`フィールドがある場合、`str`の代わりにPydanticの`HttpUrl`を指定することができます:

```Python hl_lines="4 10"

 *
 * All start/connect/acquire events will eventually receive a matching end/release event, either
 * successful (non-null parameters), or failed (non-null throwable). The first common parameters of
 * each event pair are used to link the event in case of concurrent or repeated events e.g.
 * `dnsStart(call, domainName)` → `dnsEnd(call, domainName, inetAddressList)`.
 *
 * Events are typically nested with this structure:
 *

      Header("if-modified-since", ""),
      Header("if-none-match", ""),
      Header("if-range", ""),
      Header("if-unmodified-since", ""),
      Header("last-modified", ""),
      Header("link", ""),
      Header("location", ""),
      Header("max-forwards", ""),
      Header("proxy-authenticate", ""),
      Header("proxy-authorization", ""),
      Header("range", ""),
      Header("referer", ""),

        array[i++] = (Integer) e;
      }
      return create(array);
    }

    /**
     * Creates a new collection containing the given elements; implement this method instead of
     * {@link #create(Object...)}.
     */
    protected abstract List<Integer> create(Integer[] elements);

    @Override
    public Integer[] createArray(int length) {
      return new Integer[length];
    }

    Comparator<? super K> keyComparator = (Comparator<? super K>) Comparable::compareTo;
    sort(insertionOrder, entryComparator(keyComparator));
    return insertionOrder;
  }

  /**
   * Private replacement for {@link com.google.gwt.user.client.rpc.GwtTransient} to work around
   * build-system quirks.
   */
  private @interface GwtTransient {}

  /**

import java.lang.reflect.Field;
import java.nio.charset.Charset;
import java.nio.charset.UnsupportedCharsetException;
import java.util.Arrays;
import junit.framework.TestCase;

/**
 * Tests for {@link MediaType}.
 *
 * @author Gregory Kick
 */
@GwtCompatible(emulated = true)
public class MediaTypeTest extends TestCase {
  @J2ktIncompatible
  @GwtIncompatible // reflection

        array[i++] = (Double) e;
      }
      return create(array);
    }

    /**
     * Creates a new collection containing the given elements; implement this method instead of
     * {@link #create(Object...)}.
     */
    protected abstract List<Double> create(Double[] elements);

    @Override
    public Double[] createArray(int length) {
      return new Double[length];
    }

import java.util.List;
import java.util.Set;
import java.util.function.BiPredicate;
import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;

/**
 * Tests for {@link ImmutableSortedMultiset}.
 *
 * @author Louis Wasserman
 */
public class ImmutableSortedMultisetTest extends TestCase {
  public static Test suite() {
    TestSuite suite = new TestSuite();

import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Unit test for {@link MinMaxPriorityQueue}.
 *
 * @author Alexei Stolboushkin
 * @author Sverre Sundsdal
 */
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault
public class MinMaxPriorityQueueTest extends TestCase {

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