fix link

content/docs/modules/week4/_index.md

@@ -23,7 +23,7 @@ description: Assess which data is available at your chosen data source, and whet
 - Please start working on [team activity #3](/docs/project/workplan/activity3.md)
 
 ## Self-study and activities
-- After-class exercises (<a href = 'apis101/api-101.ipynb' download>download</a>, [Google Colab](https://colab.research.google.com/github/hannesdatta/course-odcm/blob/master/content/docs/modules/week4/apis101/apis101/api-101.ipynb))
+- After-class exercises (<a href = 'apis101/api-101.ipynb' download>download</a>, [Google Colab](https://colab.research.google.com/github/hannesdatta/course-odcm/blob/master/content/docs/modules/week4/apis101/api-101.ipynb))
 
 - Please prepare [team activity #3](../../../docs/project/workplan/activity3.md).
 - Please work through challenges #3.1-#3.3 in "Fields of Gold".