updated docker file

Dockerfile

@@ -0,0 +1,12 @@
+FROM nikolaik/python-nodejs:latest
+
+# Install dependencies.
+ADD requirements.txt /requirements.txt
+ADD main.py /main.py
+ADD loc.py /loc.py
+ADD make_bar_graph.py /make_bar_graph.py
+ADD colors.json /colors.json
+RUN pip install -r requirements.txt
+RUN npm install vega-lite vega-cli canvas
+
+ENTRYPOINT ["python", "/main.py"]