# Dependencies - `Depends()` and `Security()`

## `Depends()`

Dependencies are handled mainly with the special function `Depends()` that takes a callable.

Here is the reference for it and its parameters.

You can import it directly from `fastapi`:

```python
from fastapi import Depends
```

::: fastapi.Depends

## `Security()`

) (dataErrsByDisk map[int][]int, dataErrsByPart map[int][]int) {
	dataErrsByDisk = make(map[int][]int, len(onlineDisks))
	for i := range onlineDisks {
		dataErrsByDisk[i] = make([]int, len(latestMeta.Parts))
	}

	dataErrsByPart = make(map[int][]int, len(latestMeta.Parts))
	for i := range latestMeta.Parts {
		dataErrsByPart[i] = make([]int, len(onlineDisks))
	}

	inconsistent := 0
	for i, meta := range partsMetadata {

   * satisfied at the time of signal, and has since been modified by some other thread to be
   * non-satisfied before reacquiring the lock, and that other thread takes over the responsibility
   * of signaling the next waiter.
   *
   * Unlike the underlying Condition, if we are not careful, an interrupt *can* cause a signal to be

        run: |
          sudo sysctl net.ipv6.conf.all.disable_ipv6=0
          sudo sysctl net.ipv6.conf.default.disable_ipv6=0
          make verify-healing
          make verify-healing-inconsistent-versions
          make verify-healing-with-root-disks

that if active-active replication is set up with delete marker replication, there is potential for duplicate delete markers to be created if both source and target concurrently set a Delete Marker or if one/both of the clusters went down at tandem before the replication event was synced.This is an unavoidable side-effect in active-active replication caused by allowing delete markers set on a object version with `REPLICA` status back to source.

In the case of versioned deletes a.k.a permanent...

	newFormats := make([][]*formatErasureV3, setCount)
	for i := range refFormat.Erasure.Sets {
		newFormats[i] = make([]*formatErasureV3, setDriveCount)
	}
	currentDisksInfo := make([][]DiskInfo, setCount)
	for i := range refFormat.Erasure.Sets {
		currentDisksInfo[i] = make([]DiskInfo, setDriveCount)
	}
	for i := range refFormat.Erasure.Sets {

    // Write the tagClass, tag, and constructed bit. This takes 1 byte if tag is less than 31.
    if (tag < 31) {
      val byte0 = tagClass or constructedBit or tag.toInt()
      sink.writeByte(byte0)
    } else {
      val byte0 = tagClass or constructedBit or 0b0001_1111
      sink.writeByte(byte0)
      writeVariableLengthLong(tag)
    }

    // Write the length. This takes 1 byte if length is less than 128.

 *       values for a particular key, and has <i>partially order-dependent equality</i> as defined
 *       by {@link ListMultimap#equals(Object)}. {@code ListMultimap} takes its name from the fact
 *       that the {@linkplain ListMultimap#get collection of values} associated with a given key
 *       fulfills the {@link java.util.List} contract.
 *   <dt>{@link SetMultimap}

 *       values for a particular key, and has <i>partially order-dependent equality</i> as defined
 *       by {@link ListMultimap#equals(Object)}. {@code ListMultimap} takes its name from the fact
 *       that the {@linkplain ListMultimap#get collection of values} associated with a given key
 *       fulfills the {@link java.util.List} contract.
 *   <dt>{@link SetMultimap}

		case err != nil && err != test.expError:
			t.Errorf("Test %d: Expected error: %v, but got: %v", i, test.expError, err)
		}
	}
}

// TestXLStorageFormatFileChange - to test if changing the diskID makes the calls fail.
func TestXLStorageFormatFileChange(t *testing.T) {
	volume := "fail-vol"
	xlStorage, _, err := newXLStorageTestSetup(t)
	if err != nil {
		t.Fatalf("Unable to create xlStorage test setup, %s", err)