[Python 2's EOL on January 1, 2020](https://www.python.org/dev/peps/pep-0373/#update).

Coinciding with this change, new releases of
[TensorFlow's Docker images](https://hub.docker.com/r/tensorflow/tensorflow/)
provide Python 3 exclusively. Because all images now use Python 3, Docker tags
containing `-py3` will no longer be provided and existing `-py3` tags like
`latest-py3` will not be updated.

## Major Features and Improvements

Hans Dockter <******@****.***>
Hans Dockter <******@****.***> <hans.dockter@gradleware.com>
Hans Dockter <******@****.***> <hans@Hans-Dockters-MacBook-Pro.local>
Hans Dockter <******@****.***> <******@****.***>
Hans Dockter <******@****.***> <hd@hd-desktop.(none)>
Hans Dockter <******@****.***> <mail@dockter.biz>
Hans Dockter <******@****.***> U-WIN-T79U3J3QLBC\Hans Dockter <Hans Dockter@WIN-T79U3J3QLBC.(none)>

			g := Granted{index: index}
			if c == nil {
				log("dsync: nil locker\n")
				ch <- g
				return
			}

			var locked bool
			var err error
			if isReadLock {
				if locked, err = c.RLock(netLockCtx, args); err != nil {
					log("dsync: Unable to call RLock failed with %s for %#v at %s\n", err, args, c)
				}
			} else {
				if locked, err = c.Lock(netLockCtx, args); err != nil {

 */
@GwtCompatible
public abstract class Ticker {
  /** Constructor for use by subclasses. */
  protected Ticker() {}

  /** Returns the number of nanoseconds elapsed since this ticker's fixed point of reference. */
  public abstract long read();

  /**
   * A ticker that reads the current time using {@link System#nanoTime}.
   *
   * @since 10.0
   */
  public static Ticker systemTicker() {
    return SYSTEM_TICKER;
  }

		TimeLastRefresh: UTCNow().UnixNano(),
	}

	locker.ll.lockMap["name"] = []lockRequesterInfo{
		lockRequesterInfo1,
		lockRequesterInfo2,
	}

	lri := locker.ll.lockMap["name"]

	// test unknown uid
	if locker.ll.removeEntry("name", dsync.LockArgs{
		Owner: "owner",
		UID:   "unknown-uid",
	}, &lri) {
		t.Errorf("Expected %#v, got %#v", false, true)
	}

	if !locker.ll.removeEntry("name", dsync.LockArgs{

	}
}

func TestSimpleWriteLockTimedOut(t *testing.T) {
	locked := testSimpleWriteLock(t, time.Second)

	expected := false
	if locked != expected {
		t.Errorf("TestSimpleWriteLockTimedOut(): \nexpected %#v\ngot      %#v", expected, locked)
	}
}

func testDualWriteLock(t *testing.T, duration time.Duration) (locked bool) {
	ctx := t.Context()
	lrwm := NewLRWMutex()

	//   locker: A synchronization lock that is unlocked after initialization to avoid deadlocks.
	// Returns:
	//   *Stmt: A newly created statement object for executing SQL operations.
	//   error: An error if the statement preparation fails.
	New(ctx context.Context, key string, isTransaction bool, connPool ConnPool, locker sync.Locker) (*Stmt, error)

	// Make sure only 1 callhome is running on the cluster.
	locker := objAPI.NewNSLock(minioMetaBucket, "callhome/runCallhome.lock")
	lkctx, err := locker.GetLock(ctx, callhomeLeaderLockTimeout)
	if err != nil {
		// lock timedout means some other node is the leader,
		// cycle back return 'true'
		return true
	}

	ctx = lkctx.Context()
	defer locker.Unlock(lkctx)

})

type sharedLock struct {
	lockContext chan LockContext
}

func (ld sharedLock) backgroundRoutine(ctx context.Context, objAPI ObjectLayer, lockName string) {
	for {
		locker := objAPI.NewNSLock(minioMetaBucket, lockName)
		lkctx, err := locker.GetLock(ctx, sharedLockTimeout)
		if err != nil {
			continue
		}

	keepLock:
		for {
			select {
			case <-ctx.Done():
				return
			case <-lkctx.Context().Done():

    //            (__)\       )\/\
    //                ||----w |
    //                ||     ||
    Runnable state = get();
    Blocker blocker = null;
    while (state instanceof Blocker || state == PARKED) {
      if (state instanceof Blocker) {
        blocker = (Blocker) state;
      }
      spinCount++;
      if (spinCount > MAX_BUSY_WAIT_SPINS) {
        /*