code: def stop_dashboard_api(self):
      if self.dashboard_api_process is None:
          return None
  
      self.dashboard_api_process.kill()
      self.dashboard_api_process = None
  
      atexit.unregister(self._handle_signal_dashboard_api)
  
imports: from serpent.utilities import SerpentError, is_windows, wait_for_crossbar
  from serpent.config import config
  import time
  import subprocess
  import shlex
  import signal
  import atexit
label_desc: Use image node_id 7 for calling the DashboardApp obj's underlying member method code with example usage: obj.stop_dashboard_api() and returns: None