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- The templates (many of them, anyway) are in the edx-platform repo.
- The templates are .yaml files that use HTML markup.
- An example, .../common/lib/xmodule/xmodule/templates/formularesponseproblem/numericalresponse.yaml, gives you a clue as to how hard these are to find: this one is for what we call "Numerical Input" problems.
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