Update associations-linking-models-together.rst
Merge pull request #1212 from alanfgh/patch-12

Update associations-linking-models-together.rst
Update retrieving-your-data.rst
Merge pull request #1213 from alanfgh/patch-13

Update retrieving-your-data.rst
Update testing.rst
Merge pull request #1214 from yukisov/patch-1

Fix typo
Update testing.rst

This will be helpful for any new candidate. As you already written for Model.
Merge pull request #1216 from aavrug/patch-13

Update testing.rst
Update testing.rst

These are just same as previous.
Merge pull request #1217 from aavrug/patch-14

Update testing.rst
Fix typo
Merge pull request #1219 from yukisov/patch-2

Fix typo