code: def del_preset(self, name):
          
          policy = self.policy
          if not policy.find_preset(name):
              self.ui_log.error("Preset '%s' not found" % name)
              return False
  
          try:
              policy.del_preset(name=name)
          except Exception as e:
              self.ui_log.error(str(e) + "\n")
              return False
  
          self.ui_log.info("Deleted preset '%s'\n" % name)
          return True
docs: Delete a named command line preset.
  
              :param name: the name of the preset to delete
              :returns: True on success or False otherwise