title: Getting specfic values related to result after using pythonwekawrapper3
body: <p>I am using Pythonwekawrapper3 for attribute selection so i can remove the remaining attributes and use selected ones in python code to make an ensemble learner on it. But i am facing a problem in getting "Selected attributes:" part only from results the weka wrapper gives. What i want is a variable with all the selected attributes in it but I don't know how.</p>
  
  <p>I have searched all over web for it but unable to find a way to get on selected attributes only from result_string. </p>
  
  <pre><code>search = ASSearch(classname="weka.attributeSelection.GeneticSearch", options=["-Z", "50", "-G", "100", "-C", "0.9","-M", "0.1"])
  evaluator = ASEvaluation(classname="weka.attributeSelection.CfsSubsetEval", options=["-P", "1", "-E", "1"])
  attsel = AttributeSelection()
  attsel.search(search)
  attsel.evaluator(evaluator)
  attsel.select_attributes(data)
  
  print("# attributes: " + str(attsel.number_attributes_selected))
  print("attributes: " + str(attsel.selected_attributes))
  print("result string:\n" + attsel.results_string)
  </code></pre>
  
  <p>|Selected attributes: 2,3,7,8,9,10,11,12,13 #</p>
  
  <p>variable=[2,3,7,8,9,10,11,12,13]</p>