anchor.diff:  # advantage of its cache, which greatly speeds up subsequent builds.
   
   RUN apt-get update \
  -    && apt-get install -y \
  +    && apt-get install --no-install-recommends --no-install-suggests -y \
           apg \
           curl \
           git-core \
  
positive.code: # Builds the python-minecraft-student Docker image. Each student will
  # get their own container built from this image.
  
  FROM ubuntu:14.04
  MAINTAINER Mike McCallister <mike@mccllstr.com>
  
  # ----------------------------------------------------------------------------
  
negative.code:         openssl \
          psmisc \
          python-imaging \
          python-pip \
          python-pygame \
          supervisor \
          tmux \
          unzip \
          zip \
      && apt-get clean \
      && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*
  
  
  # ----------------------------------------------------------------------------
  