Improving reproducibility of Python and R scripts

Main points to get across:

• Put all imports in the script. Developing in the REPL means this is often missed.
• Be sure scripts work outside of the REPL. For example, test in a venv
• For Python, always provide a requirements.txt.
• For R, packrat? Provide the packrat.lock file? Or devtools
• Prefer dependencies from pypi/cran. If you must install from github, try to “pin” to the specific commit.