original_docstring: 
          Callback when strategy is started.
          
docstring: Callback when strategy is started.
docstring_tokens: Callback when strategy is started .
code: def on_start(self):
          """
          Callback when strategy is started.
          """
          self.write_log("策略启动")
code_tokens: def on_start ( self ) : self . write_log ( "策略启动") 
short_docstring: Callback when strategy is started.
short_docstring_tokens: Callback when strategy is started .
comment: """
          Callback when strategy is started.
          """