refactor,chore(egen) : refactored code as per template guidelines , performed linter test

[Jayakrishna2801]

This PR includes
1.changed REGION to LOCATION
2.removed os module
3.removed os.env(IS_TESTING) in cleanup section
4. performed linter test
5. followed template guidelines

REQUIRED: Fill out the below checklists or remove if irrelevant

1. If you are opening a PR for Official Notebooks under the notebooks/official folder, follow this mandatory checklist:

• Use the notebook template as a starting point.
• Follow the style and grammar rules outlined in the above notebook template.
• Verify the notebook runs successfully in Colab since the automated tests cannot guarantee this even when it passes.
• Passes all the required automated checks. You can locally test for formatting and linting with these instructions.
• You have consulted with a tech writer to see if tech writer review is necessary. If so, the notebook has been reviewed by a tech writer, and they have approved it.
• This notebook has been added to the CODEOWNERS file under the Official Notebooks section, pointing to the author or the author's team.
• The Jupyter notebook cleans up any artifacts it has created (datasets, ML models, endpoints, etc) so as not to eat up unnecessary resources.

[review-notebook-app]

Check out this pull request on 

See visual diffs & provide feedback on Jupyter Notebooks.

---

Powered by ReviewNB

[gericdong]

/gcbrun

[kittyabs]

several needed edits

[kittyabs]

small edit

[katiemn]

/gcbrun

[katiemn]

/gcbrun