executor.shutdown();

            // Some requests should be rejected due to backpressure
            assertTrue(rejectedCount.get() > 0, "Some requests should be rejected by backpressure");
            assertTrue(successCount.get() > 0, "Some requests should succeed");
            assertEquals(5, rejectedCount.get() + successCount.get(), "Total should be 5");

The next sections assume you already read the main [Tutorial - User Guide: Security](../../tutorial/security/index.md).

**projects depend on**. That's very difficult to manage. And you would probably end up running some projects with some **incompatible versions** of the packages, and not knowing why something isn't working.

Also, depending on your operating system (e.g. Linux, Windows, macOS), it could have come with Python already installed. And in that case it probably had some packages pre-installed with some specific versions **needed by your system**. If you install packages in the global Python environment,...

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Some text with a link to [FastAPI](https://fastapi.tiangolo.com).

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Two links here: [How to](https://fastapi.tiangolo.com/how-to/) and [Project Generators](project-generation.md){.internal-link target=_blank}.

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Another link: [**FastAPI** Project Generators](project-generation.md "Link title"){.internal-link target=_blank} with title.

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Asynchronous code just means that the language 💬 has a way to tell the computer / program 🤖 that at some point in the code, it 🤖 will have to wait for *something else* to finish somewhere else. Let's say that *something else* is called "slow-file" 📝.

So, during that time, the computer can go and do some other work, while "slow-file" 📝 finishes.

	// Create a buffer to write our archive to.
	buf := new(bytes.Buffer)

	// Create a new zip archive.
	w := zip.NewWriter(buf)

	// Add some files to the archive.
	var files = []struct {
		Name, Body string
	}{
		{"readme.txt", "This archive contains some text files."},
		{"gopher.txt", "Gopher names:\nGeorge\nGeoffrey\nGonzo"},
		{"todo.txt", "Get animal handling licence.\nWrite more examples."},
	}

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