added env port var

Dockerfile

@@ -3,14 +3,16 @@ FROM python:3.8
 MAINTAINER SakethChandra "https://github.com/Saketh-Chandra/"
 
 RUN apt-get -y install git
-# RUN apt-get install python3 -y
-# RUN apt install python3-pip -y
+RUN apt-get install python3 -y
+RUN apt install python3-pip -y
 
 RUN git clone https://github.com/Saketh-Chandra/Covid-19_website.git
 
 WORKDIR /Covid-19_website/
 
 RUN pip3 install --trusted-host pypi.python.org --requirement requirements.txt
 
+ENV port=5000
+
 # ENTRYPOINT Flask_APP=/Covid-19_website/app.py flask run --host=0.0.0.0
-CMD gunicorn --bind 0.0.0.0:5000 app:app
+CMD gunicorn --bind 0.0.0.0:$port app:app