Update ASSISTments2017.ipynb

[talibaisi]

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Description

(Brief description on what this PR is about)

What does this implement/fix? Explain your changes.

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Pull request type

• [DATASET] Add a new dataset
• [BUGFIX] Bugfix
• [FEATURE] New feature (non-breaking change which adds functionality)
• [BREAKING] Breaking change (fix or feature that would cause existing functionality to not work as expected)
• [STYLE] Code style update (formatting, renaming)
• [REFACTOR] Refactoring (no functional changes, no api changes)
• [BUILD] Build related changes
• [DOC] Documentation content changes
• [OTHER] Other (please describe):

Changes

• Feature1, tests, (and when applicable, API doc)
• Feature2, tests, (and when applicable, API doc)

or

• Fix1, tests
• Fix2, tests

Does this close any currently open issues?

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Any relevant logs, error output, etc?

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Checklist

Before you submit a pull request, please make sure you have to following:

Essentials

• PR's title starts with a category (e.g. [BUGFIX], [FEATURE], [BREAKING], [DOC], etc)
• Changes are complete (i.e. I finished coding on this PR)
• All changes have test coverage and al tests passing
• Code is well-documented (extended the README / documentation, if necessary)
• If this PR is your first one, add your name and github account to AUTHORS.md

Comments

• If this change is a backward incompatible change, why must this change be made.
• Interesting edge cases to note here