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index.md

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 This Library Carpentry lesson introduces librarians to working with data. At the conclusion of the lesson you will: understand terms, phrases, and concepts in software development and data science; identify and use best practice in data structures; use regular expressions in searches
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 > ## Prerequisites
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 > This lesson has no prerequisites. Ideally you will need a laptop and an internet connection, though this is not requried.
+{: .prereq}
 
 [contributing]: {{ site.repo }}/blob/gh-pages/CONTRIBUTING.md