```python
from fastapi import Depends
```

::: fastapi.Depends

## `Security()`

For many scenarios, you can handle security (authorization, authentication, etc.) with dependencies, using `Depends()`.

But when you want to also declare OAuth2 scopes, you can use `Security()` instead of `Depends()`.

You can import `Security()` directly from `fastapi`:

```python
from fastapi import Security
```

@GwtCompatible
public enum CollectionFeature implements Feature<Collection> {
  /**
   * The collection must not throw {@code NullPointerException} on calls such as {@code
   * contains(null)} or {@code remove(null)}, but instead must return a simple {@code false}.
   */
  ALLOWS_NULL_QUERIES,
  ALLOWS_NULL_VALUES(ALLOWS_NULL_QUERIES),

  /**
   * Indicates that a collection disallows certain elements (other than {@code null}, whose validity

  static final Random RANDOM_SOURCE = new Random(314159265358979L);
  static final int MAX_EXPONENT = 100;

  /*
   * Duplicated from LongMath.
   * binomial(biggestBinomials[k], k) fits in a long, but not
   * binomial(biggestBinomials[k] + 1, k).
   */
  static final int[] biggestBinomials = {
    Integer.MAX_VALUE,
    Integer.MAX_VALUE,
    Integer.MAX_VALUE,
    3810779,
    121977,
    16175,

    }

    // Normalize hostname and pattern by turning them into absolute domain names if they are not
    // yet absolute. This is needed because server certificates do not normally contain absolute
    // names or patterns, but they should be treated as absolute. At the same time, any hostname
    // presented to this method should also be treated as absolute for the purposes of matching
    // to the server certificate.

  public void testFromStringUnusedDefaultPort() {
    // Default port, but unused.
    checkFromStringCase("gmail.com:81", 77, "gmail.com", 81, true);
    checkFromStringCase("192.0.2.2:83", 77, "192.0.2.2", 83, true);
    checkFromStringCase("[2001::2]:85", 77, "2001::2", 85, true);
  }

  public void testFromStringNonAsciiDigits() {
    // Same as testFromStringUnusedDefaultPort but with Gujarati digits for port numbers.

  public void testFromStringUnusedDefaultPort() {
    // Default port, but unused.
    checkFromStringCase("gmail.com:81", 77, "gmail.com", 81, true);
    checkFromStringCase("192.0.2.2:83", 77, "192.0.2.2", 83, true);
    checkFromStringCase("[2001::2]:85", 77, "2001::2", 85, true);
  }

  public void testFromStringNonAsciiDigits() {
    // Same as testFromStringUnusedDefaultPort but with Gujarati digits for port numbers.

      throws ExecutionException {
    try {
      return future.get();
    } catch (InterruptedException e) {
      // Should never be thrown in GWT but play it safe
      throw new IllegalStateException(e);
    }
  }

 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *

		case err == nil && test.expError != nil:
			t.Errorf("Test %d: Expected error %v but got none.", i, test.expError)
		case err == nil && n != int64(test.length):
			t.Errorf("Test %d: %d bytes were expected, but %d were written", i, test.length, n)
		case err == nil && !bytes.Equal(data[test.offset:test.offset+test.length], buffer):
			t.Errorf("Test %d: Expected bytes: %v, but got: %v", i, data[test.offset:test.offset+test.length], buffer)

   *
   * <p>If the returned map doesn't contain all requested {@code keys} then the entries it does
   * contain will be cached, but {@code getAll} will throw an exception. If the returned map
   * contains extra keys not present in {@code keys} then all returned entries will be cached, but
   * only the entries for {@code keys} will be returned from {@code getAll}.
   *