code: def clean(self, remove_working_directory=True):
          
          if remove_working_directory is not None:
              self.log(u"Removing working directory... ")
              gf.delete_directory(self.working_directory)
              self.working_directory = None
              self.log(u"Removing working directory... done")
          self.log(u"Removing temporary directory... ")
          gf.delete_directory(self.tmp_directory)
          self.tmp_directory = None
          self.log(u"Removing temporary directory... done")
docs: Remove the temporary directory.
          If ``remove_working_directory`` is ``True``
          remove the working directory as well,
          otherwise just remove the temporary directory.
  
          :param bool remove_working_directory: if ``True``, remove
                                                the working directory as well