Attribute Error: object has no attribute

[djwilson0495]

This is the whole error report:

Error:
pygame 2.0.0 (SDL 2.0.12, python 3.9.0)
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Traceback (most recent call last):
  File "c:\Users\djwil\Documents\python\python crash course\Projects\Alien invasion\star_sky.py", line 70, in <module>
    ai.run_game()
AttributeError: 'StarrySky' object has no attribute 'run_game'