E: Unable to locate package python3-pip docker file
....
# use this for ubuntu 14.04 or 16.04
RUN apt-get update -y && apt-get install -y software-properties-common && add-apt-repository ppa:deadsnakes/ppa
RUN apt-get update -y && apt-get install -y \
python3.6 \
python3-pip \
curl \
git
RUN pip3 install --upgrade pip
...