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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def GetUnreachableInstances(instances, ssh_key):
 """ Returns list of instances unreachable via ssh. """

  hostnames = [i.private_ip for i in instances]
  ssh_status = AreHostsReachable(hostnames, ssh_key)
  assert(len(hostnames) == len(ssh_status))
  nonresponsive_instances = [instance for (instance, ssh_ok) in
                             zip(instances, ssh_status) if not ssh_ok]
  return nonresponsive_instances