Only nginx default page showing in Docker container

Solution
#Download Python from DockerHub and use it
FROM python:3.7.4
#Set the working directory in the Docker container
WORKDIR /srv/minexample_app
#Copy the configuration files to the working directory
COPY requirements.txt .
COPY start.sh .
COPY uwsgi.ini .
#Copy the Flask app code to the working directory
COPY src/ .

#Install nginx web server
RUN apt-get clean \
    && apt-get -y update
RUN apt-get -y install nginx \
    && apt-get -y install python3-dev \
    && apt-get -y install build-essential
#Install the dependencies
RUN pip install -r requirements.txt --src /usr/local/src

#Copy nginx configuration file to the nginx folder
COPY nginx.conf /etc/nginx
#Run the container
RUN chmod +x ./start.sh
CMD ["./start.sh"]