code: def find_task_descriptor(self, task_id):
      
  
      # It is not guaranteed that the index will be task_id - 1 when --tasks is
      # used with a min/max range.
      for task_descriptor in self.task_descriptors:
        if task_descriptor.task_metadata.get('task-id') == task_id:
          return task_descriptor
      return None
docs: Returns the task_descriptor corresponding to task_id.