class_docstr: 显示 task 的速度。
class_docstr_tok: ["\u663e\u793a","task","\u7684\u901f\u5ea6\u3002"]
code: def render(self, task: "Task"):
      speed = task.speed
      if speed is None:
          return Text("-- it./s", style="progress.data.speed")
      if speed > 0.1:
          return Text(
              str(round(speed, 2)) + " it./s",
              style="progress.data.speed",
          )
      else:
          return Text(
              str(round(1 / speed, 2)) + " s/it.",
              style="progress.data.speed",
          )
  
imports: import sys
  from typing import Any, Union, Optional
  from rich.progress import Progress, Console, GetTimeCallable, get_console, TaskID, Live, Text, ProgressSample
  from rich.progress import ProgressColumn, TimeRemainingColumn, BarColumn, TimeElapsedColumn, TextColumn
  from fastNLP.envs import get_global_rank
  from .utils import is_notebook
label_desc: Use image node_id 1 for calling the SpeedColumn obj's underlying member method code with example usage: obj.render(task) and returns: Text, Text, Text