Update Dockerfile

data/Dockerfiles/dockerapi/Dockerfile

@@ -1,11 +1,13 @@
 FROM alpine:3.9
 LABEL maintainer "Andre Peters <andre.peters@servercow.de>"
 
-RUN apk add -U --no-cache python2 python-dev py-pip gcc musl-dev tzdata openssl-dev libffi-dev \
-  && pip2 install --upgrade pip \
-  && pip2 install --upgrade docker==3.0.1 flask flask-restful pyOpenSSL \
-  && apk del python-dev py2-pip gcc
+WORKDIR /app
+
+RUN apk add -U --no-cache python3 tzdata python3-dev gcc musl-dev openssl-dev libffi-dev openssl\
+  && pip3 install --upgrade pip \
+  && pip3 install --upgrade docker flask flask-restful pyOpenSSL \
+  && apk del python3-dev gcc musl-dev openssl-dev libffi-dev
 
 COPY server.py /
 
-CMD ["python2", "-u", "/server.py"]
+CMD ["python3", "-u", "/server.py"]