'Constructor.
Args:
queue: The Queue instance this QueueStatistics is for.
tasks: The number of tasks left.
oldest_eta_usec: The eta of the oldest non-completed task for the queue;
None if unknown.
executed_last_minute: The number of tasks executed in the last minute.
in_flight: The number of tasks that are currently executing.
enforced_rate: The current enforced rate. In tasks/second.'

def __init__(self, queue, tasks, oldest_eta_usec=None, executed_last_minute=None, in_flight=None, enforced_rate=None):

    self.queue = queue
    self.tasks = tasks
    self.oldest_eta_usec = oldest_eta_usec
    self.executed_last_minute = executed_last_minute
    self.in_flight = in_flight
    self.enforced_rate = enforced_rate
