docs: def update(self):
          """ Update will try to update the target directory
          w.r.t source directory. Only files that are common
          to both directories will be updated, no new files
          or directories are created """
  
          self._copyfiles = False
          self._updatefiles = True
          self._purge = False
          self._creatdirs = False
  
          if self._verbose:
              self.log('Updating directory %s with %s\n' %
                       (self._dir2, self._dir1))
          self._dirdiffandupdate(self._dir1, self._dir2)