new_contents: from pychecker2 import TestSupport
  from pychecker2 import OpChecks
  
  class OpTests(TestSupport.WarningTester):
      def testWarningSuppression(self):
          # check cmd-line warning suppression
          self.argv = ['--no-operatorPlus']
          f = self.check_file('def f(x):\n'
                              '   return +x\n')
          assert len(f.warnings) == 1
          line, warning, args = f.warnings[0]
          assert not warning.value
  
subject: test cmd-line warning suppression