Using Blame with github Website.
GitHub
1. Click on oppia/oppia to select the repo

2. Navigate to the file you want.

3. Click on core

4. Click on templates

5. Click on pages

6. Click on contact-page

7. Click on contact-page.component.html

8. Click on Blame to use the blame feature provided by github

9. click the line shown in the image to see the pr that had introduced the changes to the line.

10. you can see the commit id and the parent which is the commit it before it.
