We see that we are going to need some dependencies used in several places of the application.

So we put them in their own `dependencies` module (`app/dependencies.py`).

We will now use a simple dependency to read a custom `X-Token` header:

//// tab | Python 3.9+

```Python hl_lines="3  6-8" title="app/dependencies.py"
{!> ../../docs_src/bigger_applications/app_an_py39/dependencies.py!}
```

////

			// In this case, parity == 0 implies that this object version is a
			// delete marker
			readQuorum = N/2 + 1
		}
		if occ < readQuorum {
			// Ignore this parity since we don't have enough shards for read quorum
			continue
		}

		if occ > maxOcc {
			maxOcc = occ
			cparity = parity
		}
	}

	if maxOcc == 0 {
		// Did not found anything useful
		return -1
	}
	return cparity

private fun BufferedSource.skipRestOfLine() {
  when (val newline = indexOf('\n'.code.toByte())) {
    -1L -> skip(buffer.size) // Exhaust this source.
    else -> skip(newline + 1)
  }
}

/**
 * Reads lines from `IdnaMappingTable.txt`.
 *
 * Comment lines are either blank or start with a `#` character. Lines may also end with a comment.
 * All comments are ignored.
 *

import java.util.Map;
import org.jspecify.annotations.NonNull;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * Test cases for a {@link Table} implementation supporting reads and writes.
 *
 * @author Jared Levy
 * @author Louis Wasserman
 */
@GwtCompatible
@NullMarked
public abstract class AbstractTableTest<C extends @Nullable Character>
    extends AbstractTableReadTest<C> {

## Development { #development }

By the time I started creating **FastAPI** itself, most of the pieces were already in place, the design was defined, the requirements and tools were ready, and the knowledge about the standards and specifications was clear and fresh.

## Future { #future }

By this point, it's already clear that **FastAPI** with its ideas is being useful for many people.

		return errFileNotFound
	}
	if isSysErrIO(err) {
		return errFaultyDisk
	}
	if isSysErrInvalidArg(err) {
		storageLogIf(context.Background(), err)
		// For some odd calls with O_DIRECT reads
		// filesystems can return EINVAL, handle
		// these as FileNotFound instead.
		return errFileNotFound
	}
	if isSysErrNoSpace(err) {
		return errDiskFull
	}
	return err

	PAXRecords map[string]string

	// Format specifies the format of the tar header.
	//
	// This is set by Reader.Next as a best-effort guess at the format.
	// Since the Reader liberally reads some non-compliant files,
	// it is possible for this to be FormatUnknown.
	//
	// If the format is unspecified when Writer.WriteHeader is called,
	// then it uses the first format (in the order of USTAR, PAX, GNU)

    /**
     * Reloads the synonym dictionary from its source file.
     *
     * @param updater An optional updater to apply changes during reload.
     * @throws DictionaryException if the dictionary file cannot be read.
     */
    protected void reload(final SynonymUpdater updater) {
        try (CurlResponse curlResponse = dictionaryManager.getContentResponse(this)) {
            reload(updater, curlResponse.getContentAsStream());

		mkTest(16, 4, 8),
		// Exact simple majority consensus
		mkTest(16, 4, 9),
		// non-tiered object require read quorum of EcM
		nonTieredTest(15, 3, 12),
		// non-tiered object with fewer than EcM in consensus
		nonTieredTest(15, 3, 11),
		// non-tiered object require read quorum of EcM
		nonTieredTest(16, 4, 12),
		// non-tiered object with fewer than EcM in consensus
		nonTieredTest(16, 4, 11),
	}

                        // Last thread wipes password
                        auth.secureWipePassword();
                    } else {
                        // Other threads try to read password
                        String pwd = auth.getPassword();
                        // Password might be null if already wiped
                        assertTrue(pwd == null || pwd.equals("ConcurrentPass123!"));