# Dependencies - `Depends()` and `Security()`

## `Depends()`

Dependencies are handled mainly with the special function `Depends()` that takes a callable.

Here is the reference for it and its parameters.

You can import it directly from `fastapi`:

```python
from fastapi import Depends
```

::: fastapi.Depends

## `Security()`

import static java.util.Arrays.asList;
import static java.util.concurrent.TimeUnit.DAYS;
import static java.util.concurrent.TimeUnit.SECONDS;
import static org.junit.Assert.assertThrows;

import com.google.common.base.Function;
import com.google.common.cache.CacheBuilderFactory.DurationSpec;
import com.google.common.cache.LocalCache.Strength;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Iterables;

	"testing"

	xhttp "github.com/minio/minio/internal/http"
)

// TestGetAndValidateAttributesOpts is currently minimal and covers a subset of getAndValidateAttributesOpts(),
// it is intended to be expanded when the function is worked on in the future.
func TestGetAndValidateAttributesOpts(t *testing.T) {
	globalBucketVersioningSys = &BucketVersioningSys{}
	bucket := minioMetaBucket
	ctx := t.Context()
	testCases := []struct {

/// tip | Consejo

Puedes sobreescribir una dependencia utilizada en cualquier lugar de tu aplicación **FastAPI**.

La dependencia original podría ser utilizada en una *path operation function*, un *path operation decorator* (cuando no usas el valor de retorno), una llamada a `.include_router()`, etc.

FastAPI todavía podrá sobrescribirla.

///

import java.util.HashSet;
import java.util.List;
import java.util.Locale;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
import java.util.concurrent.ExecutionException;
import java.util.function.Consumer;
import java.util.stream.Collectors;
import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;

 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.google.common.collect;

import com.google.common.base.Function;
import com.google.common.collect.testing.Helpers.NullsBeforeTwo;
import com.google.common.collect.testing.SafeTreeMap;
import com.google.common.collect.testing.SortedMapTestSuiteBuilder;

  val b1 = this[index + 1].code
  return (b0 shl 7) + b1
}

/**
 * An extremely generic binary search that doesn't know what data it's searching over. The caller
 * provides indexes and a comparison function, and this calls that function iteratively.
 *
 * @return the index of the match. If no match is found this is `(-1 - insertionPoint)`, where the
 *     inserting the element at `insertionPoint` will retain sorted order.
 */

 * either express or implied. See the License for the specific language
 * governing permissions and limitations under the License.
 */
package org.codelibs.fess.opensearch.config.exentity;

import java.util.function.BiFunction;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.codelibs.core.lang.StringUtil;

   * enough precision.
   */
  private static final long C1 = 0xcc9e2d51;
  private static final long C2 = 0x1b873593;

  /*
   * This method was rewritten in Java from an intermediate step of the Murmur hash function in
   * http://code.google.com/p/smhasher/source/browse/trunk/MurmurHash3.cpp, which contained the
   * following header:
   *
   * MurmurHash3 was written by Austin Appleby, and is placed in the public domain. The author

import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.Arrays;
import java.util.Objects;
import java.util.function.Consumer;
import java.util.logging.Logger;

import static org.codelibs.curl.io.ContentOutputStream.PREFIX;
import static org.codelibs.curl.io.ContentOutputStream.SUFFIX;
import static org.junit.Assert.assertEquals;