code: def get_tasks(self, task_id=None, state='completed', json_file=None):
          
          if self.project is None:
              raise ProjectError
  
          loader = create_tasks_loader(self.project.id, task_id,
                                       state, json_file, self.all)
          self.tasks = loader.load()
  
          self._check_project_has_tasks()
          self.tasks_df = dataframer.create_data_frame(self.tasks)
docs: Load all project Tasks.