How to install fastai 2 on Google Colab

Part 1 (2020)
7

i executed above commands and face below issue

      1 from . import models
      2 from ..basics import *
----> 3 from ..callback.all import *
      4 from .augment import *
      5 from .core import *

ModuleNotFoundError: No module named 'fastai.callback.all'; 'fastai.callback' is not a package