anchor.diff:  RUN DEBIAN_FRONTEND=noninteractive wget \
   #    https://mirrors.nics.utk.edu/cran/src/contrib/shinystan_2.5.0.tar.gz \
   #    https://mirrors.nics.utk.edu/cran/src/contrib/rstanarm_2.17.4.tar.gz \
  -    https://mirrors.nics.utk.edu/cran/src/contrib/tidyposterior_0.0.1.tar.gz \
  +#    https://mirrors.nics.utk.edu/cran/src/contrib/tidyposterior_0.0.1.tar.gz \
       https://mirrors.nics.utk.edu/cran/src/contrib/yardstick_0.0.1.tar.gz \
       https://mirrors.nics.utk.edu/cran/src/contrib/tidymodels_0.0.1.tar.gz \
       https://mirrors.nics.utk.edu/cran/src/contrib/xgboost_0.71.2.tar.gz \
  
positive.code: RUN DEBIAN_FRONTEND=noninteractive R CMD INSTALL \
  #    shinystan_2.5.0.tar.gz \
  #    rstanarm_2.17.4.tar.gz \
      tidyposterior_0.0.1.tar.gz \
      yardstick_0.0.1.tar.gz \
      tidymodels_0.0.1.tar.gz \
      xgboost_0.71.2.tar.gz \
  
negative.code: RUN rm \
  #    shinystan_2.5.0.tar.gz \
  #    rstanarm_2.17.4.tar.gz \
  #    tidyposterior_0.0.1.tar.gz \
      yardstick_0.0.1.tar.gz \
      tidymodels_0.0.1.tar.gz \
      xgboost_0.71.2.tar.gz \
  