The error env.os

environment: something the run needs is missing or different where it runs (a package, a file, a device, the network): the error names what to install, fetch or attach.

Where MIME gives it, with what its message says happened and what its action says to do ({…} is filled in from the experiment):

• in mime/env/_check.py:

  • what happened: {…} is {…}; the base image {…} holds {…}

  • what to do: run in {…}, or check without --base

Reading an error and reaching its full traceback: reading an error. Every code: the index.