{* ../../docs_src/body/tutorial001_py310.py hl[5:9] *}


The same as when declaring query parameters, when a model attribute has a default value, it is not required. Otherwise, it is required. Use `None` to make it just optional.

For example, this model above declares a JSON "`object`" (or Python `dict`) like:

```JSON
{
    "name": "Foo",
    "description": "An optional description",
    "price": 45.2,
    "tax": 3.5

    /**
     * Retrieves a data configuration by its name.
     *
     * <p>If multiple configurations exist with the same name, returns the first one
     * ordered by sort order ascending.</p>
     *
     * @param name the name of the data configuration to retrieve
     * @return an OptionalEntity containing the DataConfig if found, empty otherwise
     * @throws IllegalArgumentException if name is null or empty
     */

      <name>PersistedToolchains</name>
      <superClass>TrackableBase</superClass>
      <description>
        The {@code &lt;toolchains&gt;} element is the root of the descriptor.
        The following table lists all the possible child elements.
      </description>
      <version>1.0.0+</version>
      <fields>
        <field>
          <name>toolchains</name>
          <version>1.0.0+</version>

    }

  /**
   * The maximum number of requests for each host to execute concurrently. This limits requests by
   * the URL's host name. Note that concurrent requests to a single IP address may still exceed this
   * limit: multiple hostnames may share an IP address or be routed through the same HTTP proxy.
   *
   * If more than [maxRequestsPerHost] requests are in flight when this is invoked, those requests
   * will remain in flight.
   *

     */
    public EditForm() {
        super();
    }

    /**
     * The name of the web configuration associated with this failure URL.
     * Used to identify which web crawling configuration encountered the failure.
     */
    public String webConfigName;

    /**
     * The name of the file configuration associated with this failure URL.

-->
<super-source path="super"/>

<inherits name="com.google.common.annotations.Annotations" />
<inherits name="com.google.common.base.Base" />
<inherits name="com.google.common.math.Math" />
<inherits name="com.google.common.primitives.Primitives" />
<inherits name="com.google.gwt.core.Core" />
<inherits name="com.google.gwt.user.User" />

-->
<super-source path="super"/>

<inherits name="com.google.common.annotations.Annotations" />
<inherits name="com.google.common.base.Base" />
<inherits name="com.google.common.collect.Collect" />
<inherits name="com.google.gwt.core.Core" />
<inherits name="com.google.gwt.user.User" />
<inherits name="com.google.thirdparty.publicsuffix.PublicSuffixType" />

-->
<super-source path="super"/>

<inherits name="com.google.common.annotations.Annotations" />
<inherits name="com.google.common.base.Base" />
<inherits name="com.google.common.collect.Collect" />
<inherits name="com.google.gwt.core.Core" />
<inherits name="com.google.gwt.user.User" />

-->
<super-source path="super"/>

<inherits name="com.google.common.annotations.Annotations" />
<inherits name="com.google.common.base.Base" />
<inherits name="com.google.common.escape.Escape" />
<inherits name="com.google.gwt.core.Core" />
<inherits name="com.google.gwt.user.User" />

        // Both instances should be of the same class
        assertEquals(exception1.getClass(), exception2.getClass());
    }

    public void test_componentNameWithSpecialCharacters() {
        // Test component name with special characters
        String componentName = "my-component_v2.0@service";