anchor.diff:  # Dockerfile for installing the necessary dependencies for building Hadoop.
   # See BUILDING.txt.
   
  -FROM ubuntu:xenial
  +FROM ubuntu:bionic
   
   WORKDIR /root
   
  
positive.code:         python-wheel \
          rsync \
          software-properties-common \
          snappy \
          sudo \
          valgrind \
          zlib1g-dev \
  
negative.code:         git \
          gnupg-agent \
          libbz2-dev \
          libfuse-dev \
          libprotobuf-dev \
          libprotoc-dev \
  