return Tables.transformValues(original, FIRST_CHARACTER);
  }

  @Override
  protected Map<String, Map<Integer, Character>> makePopulatedMap() {
    Table<Integer, String, String> table = HashBasedTable.create();
    table.put(1, "foo", "apple");
    table.put(1, "bar", "banana");
    table.put(3, "foo", "cat");
    return Tables.transformValues(table, FIRST_CHARACTER).columnMap();
  }

    return Tables.unmodifiableTable(table);
  }

  @Override
  protected Map<String, Integer> makePopulatedMap() {
    Table<Character, String, Integer> table = HashBasedTable.create();
    table.put('a', "one", 1);
    table.put('a', "two", 2);
    table.put('a', "three", 3);
    table.put('b', "four", 4);
    return Tables.unmodifiableTable(table).row('a');
  }

import com.google.common.base.Supplier;
import java.util.Map;
import java.util.TreeMap;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Test cases for {@link Tables#newCustomTable}.
 *
 * @author Jared Levy
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public class NewCustomTableTest extends AbstractTableTest<Character> {

  @Override

	time.RFC1123,
	time.RFC1123Z,
	// Add new AMZ date formats here.
}

// ErrMalformedDate always returned for dates that cannot be parsed.
var ErrMalformedDate = errors.New("malformed date")

// Parse parses date string via supported amz date formats.
func Parse(amzDateStr string) (time.Time, error) {
	for _, dateFormat := range amzDateFormats {
		amzDate, err := time.Parse(dateFormat, amzDateStr)
		if err == nil {

		ext = tok.String()
	}
	if p.peek() == lex.LSH {
		// parses left shift amount applied after extension: <<Amount
		p.get(lex.LSH)
		tok := p.get(scanner.Int)
		amount, err := strconv.ParseInt(tok.String(), 10, 16)
		if err != nil {
			p.errorf("parsing left shift amount: %s", err)
		}
		num = int16(amount)
	} else if p.peek() == '[' {
		// parses an element: [Index]
		p.get('[')
		tok := p.get(scanner.Int)

}

// preSignValues data type represents structured form of AWS Signature V4 query string.
type preSignValues struct {
	signValues
	Date    time.Time
	Expires time.Duration
}

// Parses signature version '4' query string of the following form.
//
//	querystring = X-Amz-Algorithm=algorithm
//	querystring += &X-Amz-Credential= urlencode(accessKey + '/' + credential_scope)
//	querystring += &X-Amz-Date=date

import com.google.common.annotations.J2ktIncompatible;
import com.google.common.base.Function;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Test cases for {@link Tables#transformValues}.
 *
 * @author Jared Levy
 */
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault
public class TablesTransformValuesTest extends AbstractTableTest<Character> {

import com.google.common.annotations.J2ktIncompatible;
import com.google.common.base.Function;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Test cases for {@link Tables#transformValues}.
 *
 * @author Jared Levy
 */
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault
public class TablesTransformValuesTest extends AbstractTableTest<Character> {

## Create the tables

In this case, we are creating the tables in the same Python file, but in production, you would probably want to create them with Alembic, integrated with migrations, etc.

Here, this section would run directly, right before starting your **FastAPI** application.

* Create an `engine`.
* Create all the tables from the `metadata` object.

```Python hl_lines="25-28"

### Kompakt

Es gibt für alles sensible **Defaultwerte**, mit optionaler Konfiguration überall. Alle Parameter können feinjustiert werden, damit sie tun, was Sie benötigen, und die API definieren, die Sie brauchen.

Aber standardmäßig **„funktioniert einfach alles“**.

### Validierung

* Validierung für die meisten (oder alle?) Python-**Datentypen**, hierzu gehören: