* the collection operation is performed. (This differs from the {@code Collector} returned by
   * {@link java.util.stream.Collectors#toMap(java.util.function.Function,
   * java.util.function.Function) Collectors.toMap(Function, Function)}, which throws an {@code
   * IllegalStateException}.)
   *
   * @since 33.2.0 (available since 21.0 in guava-jre)
   */
  @SuppressWarnings("Java7ApiChecker")

   * Collectors#toMap(Function, Function)}, which throws an {@code IllegalStateException}.)
   *
   * @since 21.0
   */
  public static <T extends @Nullable Object, K, V>
      Collector<T, ?, ImmutableBiMap<K, V>> toImmutableBiMap(
          Function<? super T, ? extends K> keyFunction,
          Function<? super T, ? extends V> valueFunction) {

## Context Managers

### What are "Context Managers"

"Context Managers" are any of those Python objects that you can use in a `with` statement.

<p class="rule">
If a package <code>p</code> imports package <code>q</code>, the completion of
<code>q</code>'s <code>init</code> functions happens before the start of any of <code>p</code>'s.
</p>

<p class="rule">
The completion of all <code>init</code> functions is synchronized before
the start of the function <code>main.main</code>.
</p>

<h3 id="go">Goroutine creation</h3>

<p class="rule">

	//            C.f(_cgo0)
	//    }()
	// Using a function literal like this lets us evaluate the
	// function arguments only once while doing pointer checks.
	// This is particularly useful when passing additional arguments
	// to _cgoCheckPointer, as done in checkIndex and checkAddr.
	//
	// When the function argument is a conversion to unsafe.Pointer,

{* ../../docs_src/custom_docs_ui/tutorial001.py hl[8] *}

### Include the custom docs

Now you can create the *path operations* for the custom docs.

You can reuse FastAPI's internal functions to create the HTML pages for the docs, and pass them the needed arguments:

* `openapi_url`: the URL where the HTML page for the docs can get the OpenAPI schema for your API. You can use here the attribute `app.openapi_url`.

Si tienes bastante conocimiento técnico (coroutines, threads, bloqueos, etc.) y tienes curiosidad acerca de cómo FastAPI gestiona `async def` vs `def` normal, continúa.

///

### Path operation functions

import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.util.Collection;
import java.util.Comparator;
import java.util.Map;
import java.util.Map.Entry;
import java.util.function.Function;
import java.util.stream.Collector;
import java.util.stream.Stream;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**

import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import java.util.SortedMap;
import java.util.Spliterator;
import java.util.Spliterators;
import java.util.function.BiFunction;
import java.util.function.BinaryOperator;
import java.util.function.Function;
import java.util.stream.Collector;
import java.util.stream.Collectors;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

      extends AbstractSequentialList<T> implements Serializable {
    final List<F> fromList;
    final Function<? super F, ? extends T> function;

    TransformingSequentialList(List<F> fromList, Function<? super F, ? extends T> function) {
      this.fromList = checkNotNull(fromList);
      this.function = checkNotNull(function);
    }

    /**