import java.lang.annotation.Retention;

import static java.lang.annotation.RetentionPolicy.RUNTIME;

/**
 * Provides a unique identifier for dependencies when multiple implementations
 * of the same type are available.
 * <p>
 * This annotation can be used in conjunction with {@link Inject} to specify
 * which implementation should be injected when multiple candidates exist.

You can easily use the same Pydantic settings to configure your generated OpenAPI and the docs UIs.

For example:

{* ../../docs_src/conditional_openapi/tutorial001_py39.py hl[6,11] *}

Here we declare the setting `openapi_url` with the same default of `"/openapi.json"`.

And then we use it when creating the `FastAPI` app.

   *       (<i>symmetric</i> property)
   *   <li>If {@code equivalent(x, y)} and {@code equivalent(y, z)} are both true, then {@code
   *       equivalent(x, z)} is also true (<i>transitive</i> property)
   * </ul>
   *
   * <p>Note that all calls to {@code equivalent(x, y)} are expected to return the same result as
   * long as neither {@code x} nor {@code y} is modified.

If you pass a "callable" as a dependency in **FastAPI**, it will analyze the parameters for that "callable", and process them in the same way as the parameters for a *path operation function*. Including sub-dependencies.

That also applies to callables with no parameters at all. The same as it would be for *path operation functions* with no parameters.

        assertNotNull(instance1);
        assertNotNull(instance2);
        // The second setInstance replaces the first, so they should not be the same
        assertNotSame(instance1, instance2);
        // Getting instance again should return the same as instance2
        assertSame(instance2, LogStream.getInstance());
    }

    @Test
    void testLogStreamInheritsFromPrintStream() {

        // Assert
        assertArrayEquals(h2, h1, "nTOWFv1 should return NT hash");
        assertEquals(16, h1.length, "NT hash length is 16 bytes");
    }

    @Test
    @DisplayName("nTOWFv2: overloads produce same result and domain affects key")
    void testNTOWFv2_overloadsAndDomainSensitivity() {
        // Arrange
        String domain = "Domain";
        String user = "User";
        String password = "password";

The process that happens when your API app calls the *external API* is named a "callback". Because the software that the external developer wrote sends a request to your API and then your API *calls back*, sending a request to an *external API* (that was probably created by the same developer).

	} else if addr2Local, err = isLocalHost(host2, port2, port2); err != nil {
		// Host not empty, check if it is local
		return false, err
	}

	// If both of addresses point to the same machine, check if
	// have the same port
	if addr1Local && addr2Local {
		if port1 == port2 {
			return true, nil
		}
	}
	return false, nil
}

// CheckLocalServerAddr - checks if serverAddr is valid and local host.

You can use the same dependency *functions* you use normally.

### Dependency requirements { #dependency-requirements }

They can declare request requirements (like headers) or other sub-dependencies:

{* ../../docs_src/dependencies/tutorial006_an_py39.py hl[8,13] *}

### Raise exceptions { #raise-exceptions }

These dependencies can `raise` exceptions, the same as normal dependencies:

/**
 * A bimap (or "bidirectional map") is a map that preserves the uniqueness of its values as well as
 * that of its keys. This constraint enables bimaps to support an "inverse view", which is another
 * bimap containing the same entries as this bimap but with reversed keys and values.
 *
 * <h3>Implementations</h3>
 *
 * <ul>
 *   <li>{@link ImmutableBiMap}
 *   <li>{@link HashBiMap}
 *   <li>{@link EnumBiMap}