# Primeros Pasos { #first-steps }

El archivo FastAPI más simple podría verse así:

{* ../../docs_src/first_steps/tutorial001_py39.py *}

Copia eso en un archivo `main.py`.

Ejecuta el servidor en vivo:

<div class="termy">

```console
$ <font color="#4E9A06">fastapi</font> dev <u style="text-decoration-style:solid">main.py</u>

      assertThat(cache.asMap().entrySet()).containsExactly(immutableEntry(key2, value2));
    }
  }

  // fails in Maven with 64-bit JDK: https://github.com/google/guava/issues/1568

  // A simple type whose .toString() will return the same value each time, but without maintaining
  // a strong reference to that value.
  static class Key {
    private final int value;
    private WeakReference<String> toString;

        when(mockReferral.getPathConsumed()).thenReturn(15); // e.g., "\\\\server\\share".length()
        when(mockReferral.next()).thenReturn(mockReferral); // Simple loop for the do-while
        assertDoesNotThrow(() -> dfsImpl.cache(mockContext, "\\\\server\\share\\path", mockReferral));
    }

@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

import org.apache.maven.api.annotations.Nullable;

/**
 * Describes a problem that was encountered during project building. A problem can either be an exception that was
 * thrown or a simple string message. In addition, a problem carries a hint about its source.
 *
 * @since 4.0.0
 */
@Experimental
@Immutable
public interface BuilderProblem {

    /**

        Maven maven = getContainer().lookup(Maven.class);
        MavenExecutionRequest request =
                createMavenExecutionRequest(getProject("simple")).setGoals(asList("validate"));

        MavenExecutionResult result = maven.execute(request);
        assertNotNull(result);

        Class<?> wsrClass = wsrClassCatcher.wsrClassRef.get();

package asm

import (
	"cmd/asm/internal/lex"
	"strings"
	"testing"
	"text/scanner"
)

type exprTest struct {
	input  string
	output int64
	atEOF  bool
}

var exprTests = []exprTest{
	// Simple
	{"0", 0, true},
	{"3", 3, true},
	{"070", 8 * 7, true},
	{"0x0f", 15, true},
	{"0xFF", 255, true},
	{"9223372036854775807", 9223372036854775807, true}, // max int64
	// Unary
	{"-0", 0, true},

}

var (
	D        MultiFlag
	I        MultiFlag
	PrintOut int
	DebugV   bool
)

func init() {
	flag.Var(&D, "D", "predefined symbol with optional simple value -D=identifier=value; can be set multiple times")
	flag.Var(&I, "I", "include directory; can be set multiple times")
	flag.BoolVar(&DebugV, "v", false, "print debug output")

        byte[] reusedBuffer = testCache.getBuffer();

        // Then
        assertSame(originalBuffer, reusedBuffer, "Released buffer should be reused");
    }

    /**
     * Simple test implementation of BufferCache for testing purposes
     */
    private static class TestBufferCacheImpl implements BufferCache {
        private final List<byte[]> cache;
        private final int bufferSize;

					Value: "minio123",
				},
			},
		},
		{
			`
export MINIO_ROOT_USERminio
export MINIO_ROOT_PASSWORD=minio123`,
			true,
			nil,
		},
		{
			`
# simple comment
# MINIO_ROOT_USER=minioadmin
# MINIO_ROOT_PASSWORD=minioadmin
MINIO_ROOT_USER=minio
MINIO_ROOT_PASSWORD=minio123`,
			false,
			[]envKV{
				{
					Key:   "MINIO_ROOT_USER",