```Python
with open("./somefile.txt") as f:
    contents = f.read()
    print(contents)
```

Под капотом" open("./somefile.txt") создаёт объект называемый "контекстным менеджером".

Когда блок `with` завершается, он обязательно закрывает файл, даже если были исключения.

   * EPUB is the distribution and interchange format standard for digital publications and
   * documents. This media type is defined in the <a
   * href="http://www.idpf.org/epub/30/spec/epub30-ocf.html">EPUB Open Container Format</a>
   * specification.
   *
   * @since 15.0
   */
  public static final MediaType EPUB = createConstant(APPLICATION_TYPE, "epub+zip");

  public static final MediaType FORM_DATA =

            return null;
        }).when(mockDcerpcHandle).sendrecv(any(MsrpcLsarClose.class));

        // Act
        handle.close();

        // Assert
        // Verify sendrecv was called once for open and once for close
        verify(mockDcerpcHandle, times(1)).sendrecv(any(MsrpcLsarOpenPolicy2.class));
        verify(mockDcerpcHandle, times(1)).sendrecv(any(MsrpcLsarClose.class));
    }

    @Test

So, it was a complete additional system.

It is not very popular or used nowadays.

## OpenAPI { #openapi }

OpenAPI (previously known as Swagger) is the open specification for building APIs (now part of the Linux Foundation).

**FastAPI** is based on **OpenAPI**.

That's what makes it possible to have multiple automatic interactive documentation interfaces, code generation, etc.

        buf.append("\"process\":{");
        final ProcessProbe processProbe = ProcessProbe.getInstance();
        buf.append("\"file_descriptor\":{");
        append(buf, "open", () -> processProbe.getOpenFileDescriptorCount()).append(',');
        append(buf, "max", () -> processProbe.getMaxFileDescriptorCount());
        buf.append("},");
        buf.append("\"cpu\":{");

/*
 * Copyright (C) 2012 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,

 * are "allowed". If all of the desired access bits are not "allowed"
 * the then same process is repeated for inherited ACEs.
 * <p>
 * For example, if user <code>WNET\alice</code> tries to open a file
 * with desired access bits <code>0x00000003</code> (<code>FILE_READ_DATA |
 * FILE_WRITE_DATA</code>) and the target file has the following security
 * descriptor ACEs:
 *
 * <pre>

     * @param len the number of bytes to write
     */
    public final void setParam(final int fid, final long offset, final int remaining, final byte[] b, final int off, final int len) {
        this.fid = fid;
        this.offset = offset;
        this.remaining = remaining;
        this.b = b;
        this.off = off;
        this.dataLength = len;
        this.digest = null; /*

import com.google.caliper.Benchmark;
import com.google.caliper.Param;
import org.jspecify.annotations.NullUnmarked;

/**
 * Benchmarks against the Apache Commons Math utilities.
 *
 * <p>Note: the Apache benchmarks are not open sourced to avoid the extra dependency.
 *
 * @author Louis Wasserman
 */
@NullUnmarked
public class ApacheBenchmark {
  private enum Impl {
    GUAVA {
      @Override

Das ist natürlich nicht optimal und man würde das nicht in der Produktion machen.

In der Produktion hätten Sie eine der oben genannten Optionen.

Aber es ist die einfachste Möglichkeit, sich auf die Serverseite von WebSockets zu konzentrieren und ein funktionierendes Beispiel zu haben:

{* ../../docs_src/websockets/tutorial001.py hl[2,6:38,41:43] *}