Cuando el bloque `with` termina, se asegura de cerrar el archivo, incluso si hubo excepciones.

Cuando creas una dependencia con `yield`, **FastAPI** creará internamente un context manager para ella y lo combinará con algunas otras herramientas relacionadas.

### Usando context managers en dependencias con `yield` { #using-context-managers-in-dependencies-with-yield }

/// warning | Advertencia

   "Contributor" means any person or entity that distributes the Program.

"Licensed Patents" mean patent claims licensable by a Contributor which are
necessarily infringed by the use or sale of its Contribution alone or when
combined with the Program.

"Program" means the Contributions distributed in accordance with this Agreement.

"Recipient" means anyone who receives the Program under this Agreement, including
all Contributors.

    checkState(
        this.maximumWeight == UNSET_INT,
        "maximum weight was already set to %s",
        this.maximumWeight);
    checkState(this.weigher == null, "maximum size can not be combined with weigher");
    checkArgument(maximumSize >= 0, "maximum size must not be negative");
    this.maximumSize = maximumSize;
    return this;
  }

  /**

### Import `FastAPI` { #import-fastapi }

You import and create a `FastAPI` class as normally.

And we can even declare [global dependencies](dependencies/global-dependencies.md) that will be combined with the dependencies for each `APIRouter`:

{* ../../docs_src/bigger_applications/app_an_py310/main.py hl[1,3,7] title["app/main.py"] *}

### Import the `APIRouter` { #import-the-apirouter }

 * <ul>
 * <li>Web crawling - crawls web sites and web content</li>
 * <li>File system crawling - crawls file systems and documents</li>
 * <li>Data store crawling - crawls databases and other data sources</li>
 * <li>Combined crawling - runs multiple crawling types simultaneously</li>
 * </ul>
 *
 * <p>Command line usage:
 * <pre>
 * java org.codelibs.fess.exec.Crawler [options...]

     * inside the {@code <source>} elements of a <abbr>POM</abbr> file.
     *
     * <h4>Application to Java</h4>
     * In the context of a Java project, this is the value given to the {@code --release} compiler option.
     * This value can determine whether a dependency will be placed on the class-path or on the module-path.
     * For example, if the {@code module-info.class} entry of a <abbr>JAR</abbr> file exists only in the

signature-android-apilevel24 = { module = "net.sf.androidscents.signature:android-api-level-24", version.ref = "signature-android-apilevel24" }
square-moshi = { module = "com.squareup.moshi:moshi", version.ref = "square-moshi" }
square-moshi-compiler = { module = "com.squareup.moshi:moshi-kotlin-codegen", version.ref = "square-moshi" }
square-moshi-kotlin = { module = "com.squareup.moshi:moshi-kotlin", version.ref = "square-moshi" }

# Download the Visual Studio 2022 Installer.
RUN (New-Object Net.WebClient).DownloadFile('https://aka.ms/vs/17/release/vs_community.exe', 'C:\TEMP\vs_community.exe');
# Install Visual Studio 2022 Build Tools + Compiler
SHELL ["cmd", "/S", "/C"]
# Packages, and component versions, can be found here:
# https://learn.microsoft.com/en-us/visualstudio/install/workload-component-id-vs-build-tools
RUN C:\TEMP\vs_community.exe \

   * input elements. Cells are inserted into the generated {@code Table} in encounter order.
   *
   * <p>If multiple input elements map to the same row and column, the specified merging function is
   * used to combine the values. Like {@link
   * java.util.stream.Collectors#toMap(java.util.function.Function, java.util.function.Function,
   * BinaryOperator, java.util.function.Supplier)}, this Collector throws a {@code

import java.util.AbstractSet;
import java.util.Arrays;
import java.util.Iterator;
import java.util.Map;
import java.util.NoSuchElementException;
import java.util.Set;

/**
 * A {@link Map} that combines the characteristics of an array.
 *
 * @author higa
 * @param <K> the type of keys
 * @param <V> the type of values
 *
 */