code: def virtualenv_exists(self, virtualenv_dir=None):
          
          r = self.local_renderer
          ret = True
          with self.settings(warn_only=True):
              ret = r.run_or_local('ls {virtualenv_dir}') or ''
              ret = 'cannot access' not in ret.strip().lower()
  
          if self.verbose:
              if ret:
                  print('Yes')
              else:
                  print('No')
  
          return ret
docs: Returns true if the virtual environment has been created.