class_docstr: Thread-safe store for node reservations.
  
  Args:
    :required: expected number of nodes in the cluster.
docstr: Returns True if the ``required`` number of reservations have been fulfilled.
docstr_tok: ["Returns","True","if","the","``","required","``","number","of","reservations","have","been","fulfilled","."]
code: def done(self):
      """Returns True if the ``required`` number of reservations have been fulfilled."""
      with self.lock:
          return len(self.reservations) >= self.required
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import nested_scopes
  from __future__ import print_function
  import logging
  import os
  import pickle
  import select
  import socket
  import struct
  import sys
  import threading
  import time
  from .None import util
label_desc: Use image node_id 3 for calling the Reservations obj's underlying member method code with example usage: obj.done() and returns: unknown