'Manager' object has no attribute 'get_tags_for'

For section Django ORM of Custom Managers #20, I am getting below error.

|Request URL:|http://127.0.0.1:8000/playground/hello/|
|Django Version:|3.2.5|
|Exception Type:|AttributeError|
|Exception Value:|‘Manager’ object has no attribute ‘get_tags_for’|

I tried to follow python - AttributeError: 'Manager' object has no attribute 'get_by_natural_key' error in Django? - Stack Overflow this solution but no success.

Please provide the solution.