if !ok {
			return Help{}, config.Errorf("unknown sub-system %s", subSys)
		}
	}

	h, ok := config.HelpSubSysMap[subSys]
	if !ok {
		return Help{}, config.Errorf("unknown sub-system %s", subSys)
	}
	if key != "" {
		value, ok := h.Lookup(key)
		if !ok {
			return Help{}, config.Errorf("unknown key %s for sub-system %s",
				key, subSys)
		}
		h = config.HelpKVS{value}
	}

   * that it can be done securely, without vulnerability to race conditions (i.e. when the file
   * system does not support {@link SecureDirectoryStream}).
   *
   * <p><b>Warning:</b> On a file system that supports symbolic links, it is possible for an
   * insecure recursive delete to delete files and directories that are <i>outside</i> the directory

        try {
            parser.parseArgument(args);
        } catch (final CmdLineException e) {
            System.err.println(e.getMessage());
            System.err.println("java " + Crawler.class.getCanonicalName() + " [options...] arguments...");
            parser.printUsage(System.err);
            return;
        }

        if (logger.isDebugEnabled()) {
            try {

## Einfach und leistungsstark

Obwohl das hierarchische Dependency Injection System sehr einfach zu definieren und zu verwenden ist, ist es dennoch sehr mächtig.

Sie können Abhängigkeiten definieren, die selbst wiederum Abhängigkeiten definieren können.

${packaging.env.file}
/etc/init.d/fess

# Get Current User { #get-current-user }

In the previous chapter the security system (which is based on the dependency injection system) was giving the *path operation function* a `token` as a `str`:

{* ../../docs_src/security/tutorial001_an_py39.py hl[12] *}

But that is still not that useful.

Let's make it give us the current user.

## Create a user model { #create-a-user-model }

First, let's create a Pydantic user model.

    version number is enough for some build systems (notably, Gradle) to select
    that empty artifact over the "real" listenablefuture-1.0 -- avoiding a
    conflict with the copy of ListenableFuture in guava itself. If users are
    using an older version of Guava or a build system other than Gradle, they
    may see class conflicts. If so, they can solve them by manually excluding

    version number is enough for some build systems (notably, Gradle) to select
    that empty artifact over the "real" listenablefuture-1.0 -- avoiding a
    conflict with the copy of ListenableFuture in guava itself. If users are
    using an older version of Guava or a build system other than Gradle, they
    may see class conflicts. If so, they can solve them by manually excluding

Linux containers run using the same Linux kernel of the host (machine, virtual machine, cloud server, etc). This just means that they are very lightweight (compared to full virtual machines emulating an entire operating system).

Then APIStar stopped to exist as a server and Starlette was created, and was a new better foundation for such a system. That was the final inspiration to build **FastAPI**.

I consider **FastAPI** a "spiritual successor" to APIStar, while improving and increasing the features, typing system, and other parts, based on the learnings from all these previous tools.

///

## Used by **FastAPI** { #used-by-fastapi }