// to retry with 503 errors when server is coming up.
			return auth.Credentials{}, false, ErrIAMNotInitialized
		}

		// Check if the access key is part of users credentials.
		u, ok, err := globalIAMSys.CheckKey(r.Context(), accessKey)
		if err != nil {
			return auth.Credentials{}, false, ErrIAMNotInitialized
		}
		if !ok {
			// Credentials could be valid but disabled - return a different
			// error in such a scenario.

				iamLogIf(ctx, logErr)
			}
		}
	}
	return skipped, nil
}

// CheckKey validates the incoming accessKey
func (sys *IAMSys) CheckKey(ctx context.Context, accessKey string) (u UserIdentity, ok bool, err error) {
	if !sys.Initialized() {
		return u, false, nil
	}

	if accessKey == globalActiveCred.AccessKey {

{!../../docs_src/dependencies/tutorial011.py!}
```

& 👈 🌌 👥 💪 "🔗" 👆 🔗, 👈 🔜 ✔️ `"bar"` 🔘 ⚫️, 🔢 `checker.fixed_content`.

## ⚙️ 👐 🔗

⤴️, 👥 💪 ⚙️ 👉 `checker` `Depends(checker)`, ↩️ `Depends(FixedContentQueryChecker)`, ↩️ 🔗 👐, `checker`, 🚫 🎓 ⚫️.

& 🕐❔ ❎ 🔗, **FastAPI** 🔜 🤙 👉 `checker` 💖:

```Python
checker(q="somequery")
```

...& 🚶‍♀️ ⚫️❔ 👈 📨 💲 🔗 👆 *➡ 🛠️ 🔢* 🔢 `fixed_content_included`:

## Use the instance as a dependency

Then, we could use this `checker` in a `Depends(checker)`, instead of `Depends(FixedContentQueryChecker)`, because the dependency is the instance, `checker`, not the class itself.

And when solving the dependency, **FastAPI** will call this `checker` like:

```Python
checker(q="somequery")
```

import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/** Implementations of {@code Futures.transform*}. */
@GwtCompatible
@ElementTypesAreNonnullByDefault
@SuppressWarnings({
  // Whenever both tests are cheap and functional, it's faster to use &, | instead of &&, ||
  "ShortCircuitBoolean",
  "nullness", // TODO(b/147136275): Remove once our checker understands & and |.
})

		b, _ := io.ReadAll(r)
		return string(b)
	}
	checkEq := func(a, b string) {
		if a != b {
			t.Fatalf("Unexpected equality failure")
		}
	}

	checkEq(readAll(NewDummyDataGen(0, 0)), "")

	checkEq(readAll(NewDummyDataGen(10, 0)), readAll(NewDummyDataGen(10, int64(len(alphabets)))))

	checkEq(readAll(NewDummyDataGen(100, 0)), readAll(NewDummyDataGen(50, 0))+readAll(NewDummyDataGen(50, 50)))

import static java.lang.Math.min;

import com.google.common.annotations.GwtCompatible;
import java.util.Map;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A {@link UnicodeEscaper} that uses an array to quickly look up replacement characters for a given
 * code point. An additional safe range is provided that determines whether code points without

   */
  protected void verify(List<E> elements) {}

  /** Executes the test. */
  @SuppressWarnings("CatchingUnchecked") // sneaky checked exception
  public final void test() {
    try {
      recurse(0);
    } catch (Exception e) { // sneaky checked exception
      throw new RuntimeException(Arrays.toString(stimuli), e);
    }
  }

  private void recurse(int level) {

import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/** Implementations of {@code Futures.catching*}. */
@GwtCompatible
@ElementTypesAreNonnullByDefault
@SuppressWarnings({
  // Whenever both tests are cheap and functional, it's faster to use &, | instead of &&, ||
  "ShortCircuitBoolean",
  "nullness", // TODO(b/147136275): Remove once our checker understands & and |.
})

import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Utilities for treating interruptible operations as uninterruptible. In all cases, if a thread is
 * interrupted during such a call, the call continues to block until the result is available or the