anchor.diff:  
   # Install Jupyter notebook as NB_USER
   RUN conda install --quiet --yes \
  -    'notebook=4.2*' \
  +    'notebook' \
       && conda clean -tipsy
   
   # Install JupyterHub to get the jupyterhub-singleuser startup script
  -RUN pip --no-cache-dir install 'jupyterhub==0.5'
  +RUN pip --no-cache-dir install 'jupyterhub'
   
   USER root
   
  
positive.code:     sudo \
      locales \
      git \
      vim \
      jed \
      emacs \
      build-essential \
      python-dev \
      unzip \
      libsm6 \
  
negative.code:     conda clean -tipsy
  
  # Install JupyterHub to get the jupyterhub-singleuser startup script
  RUN pip --no-cache-dir install 'jupyterhub'
  
  # Install Python 3 packages
  # Remove pyqt and qt pulled in for matplotlib since we're only ever going to
  # use notebook-friendly backends in these images
  RUN conda install --quiet --yes \
      'cython' \
      'numpy' \
      'pillow' \
  