return null;
        }
        return tryParseInt(s);
    }

    private static Integer tryParseInt(String s) {
        // for performance, check digits instead of relying later on catching NumberFormatException
        if (!isDigits(s)) {
            return null;
        }

        try {
            long longValue = Long.parseLong(s);

import org.codehaus.plexus.interpolation.os.OperatingSystemUtils;

/**
 *
 * @since 3.3.0
 * @deprecated since 4.0.0, use {@link org.apache.maven.api.services.ToolchainsBuilder} instead
 */
@Named
@Singleton
@Deprecated(since = "4.0.0")
public class DefaultToolchainsBuilder implements ToolchainsBuilder {
    private final org.apache.maven.api.services.ToolchainsBuilder builder;

 * all tasks, which minimizes memory footprint but also minimizes concurrency. Instead of choosing
 * either of these extremes, {@code Striped} allows the user to trade between required concurrency
 * and memory footprint. For example, if a set of tasks are CPU-bound, one could easily create a
 * very compact {@code Striped<Lock>} of {@code availableProcessors() * 4} stripes, instead of

#### Merging pull requests ####

Due to Guava's nature as a subset of Google's internal codebase which is
automatically synced to the public GitHub repository, we are unable to merge
pull requests directly into the master branch. Instead, once a pull request is
ready for merging, we'll make the appropriate changes in the internal codebase
and, when the change is synced out, give the pull request author credit for the
commit.

Contributor License Agreement

    """.trimIndent().decodeCertificatePem()

  private val client: OkHttpClient

  init {
    // This implementation just embeds the PEM files in Java strings; most applications will
    // instead read this from a resource file that gets bundled with the application.
    val certificates =
      HandshakeCertificates.Builder()
        .addTrustedCertificate(letsEncryptCertificateAuthority)

 * or a simple string message. In addition, a problem carries a hint about its source, e.g. the POM file that exhibits
 * the problem.
 *
 * @deprecated use {@link org.apache.maven.api.services.ModelBuilder} instead
 */
@Deprecated(since = "4.0.0")
public interface ModelProblem {

    /**
     * The different severity levels for a problem, in decreasing order.
     */
    enum Severity {
        FATAL, //

/**
 * Handles the import of dependency management from other models into the target model.
 *
 * @deprecated use {@link org.apache.maven.api.services.ModelBuilder} instead
 */
@Named
@Singleton
@Deprecated(since = "4.0.0")
public class DefaultDependencyManagementImporter implements DependencyManagementImporter {

    @Override
    public Model importManagement(

 Starting with Maven 3.1.0:

  *  Maven supports SLF4J API logging API too, ie {{{http://slf4j.org/apidocs/org/slf4j/LoggerFactory.html}LoggerFactory}} /
     {{{http://slf4j.org/apidocs/org/slf4j/Logger.html}Logger}},

  *  instead of implementing Plexus logging API itself with basic output to console, Maven implements it using SLF4J API in
     {{{./apidocs/org/apache/maven/cli/logging/Slf4jLoggerManager.html}Slf4jLoggerManager}}

import org.apache.maven.model.Model;
import org.apache.maven.model.Profile;

/**
 * Collects the output of the model builder.
 *
 * @deprecated use {@link org.apache.maven.api.services.ModelBuilder} instead
 */
@Deprecated(since = "4.0.0")
public interface ModelBuildingResult {

    /**
     * Gets the sequence of model identifiers that denote the lineage of models from which the effective model was

---> 100%
```

</div>

/// note

When you install with `pip install "fastapi[standard]"` it comes with some default optional standard dependencies.

If you don't want to have those optional dependencies, you can instead install `pip install fastapi`.

///

## Advanced User Guide

There is also an **Advanced User Guide** that you can read later after this **Tutorial - User guide**.