code: private Collection<AbstractMockEc2Instance> getInstances(final Set<String> instanceIDs) {
          Collection<AbstractMockEc2Instance> ret = new ArrayList<AbstractMockEc2Instance>();
          for (String instanceID : instanceIDs) {
              ret.add(getMockEc2Instance(instanceID));
          }
          return ret;
      }
docs: Get mock ec2 instances by instance IDs.
  
  @param instanceIDs
  IDs of the mock ec2 instances to get
  @return the mock ec2 instances object