Add dependency for Altair charts, #50

README.md

@@ -31,6 +31,9 @@ This project is under development! Upon it's first release, it can be installed
 pip install pydatapeek --extra-index-url=https://test.pypi.org/simple/
 ```
 
+### Dependencies:
+Note that `selenium` and `chromedriver` are needed to save Altair charts. More information on installation can be found [here](https://altair-viz.github.io/user_guide/saving_charts.html).
+
 ### Usage:
 We detail an example usage of our function below. The sample data file that we have used below can be found [here](https://github.com/UBC-MDS/PyDataPeek/blob/master/usage/example.csv). The following example assumes that the file has been downloaded as `example.csv`.