anchor.diff:  RUN wget -O archive-requirements.txt $ARCHIVE_REQUIREMENTS
   
   USER archive
  -RUN pip install --upgrade pip
  -RUN pip install --no-cache-dir --user -r archive-requirements.txt
  -RUN pip install --no-cache-dir --user -e .
  +# See also https://github.com/pypa/pip/issues/5221
  +RUN wget -O get-pip.py https://bootstrap.pypa.io/get-pip.py \
  +    && python get-pip.py --user \
  +    && rm get-pip.py
  +RUN python -m pip install --no-cache-dir --user -r archive-requirements.txt
  +RUN python -m pip install --no-cache-dir --user -e .
   
   ENV PATH $PATH:/home/archive/.local/bin
   
  
positive.code:     libxslt-dev \
      git \
      make \
      python2.7 \
      python2.7-dev \
      python-pip \
      pkg-config \
      gcc \
      zlib1g-dev \
      wget \
      tzdata \
   && rm -rf /var/lib/apt/lists/*
  
  COPY . /src/
  WORKDIR /src/
  
negative.code: FROM python:2.7-jessie
  
  RUN addgroup --system archive \
      && adduser --system --group archive
  