code: def running_instances(self, context, process_name):
          
          handle = (id(context), process_name)
          it = self.processes.get(handle, {}).itervalues()
          entries = [x for x in it if x[0].poll() is None]
          return entries
docs: Get a list of running instances.
  
          Args:
              context (`ResolvedContext`): Context the process is running in.
              process_name (str): Name of the process.
  
          Returns:
              List of (`subprocess.Popen`, start-time) 2-tuples, where start_time
              is the epoch time the process was added.