old_contents: from ppp_datamodel import Sentence
  from ppp_datamodel.communication import Request, TraceItem, Response
  from ppp_libmodule.tests import PPPTestCase
  from ppp_natural_math import app
  
  class TestFollowing(PPPTestCase(app)):
      config_var = 'PPP_NATURALMATH'
      config = ''
      def testBasics(self):
          q = Request('1', 'en', Sentence('integral of x^y'))
          r = self.request(q)
          self.assertEqual(len(r), 1, r)
          self.assertEqual(r[0].tree, Sentence('Integrate(x^y, y)'))
  
          q = Request('1', 'en', Sentence('x'))
          r = self.request(q)
          self.assertEqual(r, [])
  
          q = Request('1', 'en', Sentence('*$$!-|'))
          r = self.request(q)
          self.assertEqual(r, [])
  
new_contents: from ppp_datamodel import Sentence, Resource
  from ppp_datamodel.communication import Request, TraceItem, Response
  from ppp_libmodule.tests import PPPTestCase
  from ppp_natural_math import app
  
  class TestFollowing(PPPTestCase(app)):
      config_var = 'PPP_NATURALMATH'
      config = ''
      def testBasics(self):
          q = Request('1', 'en', Resource('x'))
          r = self.request(q)
          self.assertEqual(r, [])
  
          q = Request('1', 'en', Sentence('integral of x^y'))
          r = self.request(q)
          self.assertEqual(len(r), 1, r)
          self.assertEqual(r[0].tree, Sentence('Integrate(x^y, y)'))
  
          q = Request('1', 'en', Sentence('x'))
          r = self.request(q)
          self.assertEqual(r, [])
  
          q = Request('1', 'en', Sentence('*$$!-|'))
          r = self.request(q)
          self.assertEqual(r, [])
  
subject: Improve requesthandler test coverage.