jinja2: How to reference JSON structure items whose keys are variables?

Hello,

As the title states, the keys themselves are variables, and I’m having trouble getting values.

Instead of writing my question in the email body, I decided to create a stackexchange post:

https://devops.stackexchange.com/questions/13544/ansible-jinja2-how-to-reference-json-structure-items-whose-keys-are-variables

Any help would be appreciated, thank you,