code: def shell(environment, opts):
      
      environment.require_data()
      environment.start_supporting_containers()
      return environment.interactive_shell(
          opts['COMMAND'],
          detach=opts['--detach']
      )
docs: Run a command or interactive shell within this environment
  
  Usage:
    datacats [-d] [-s NAME] shell [ENVIRONMENT [COMMAND...]]
  
  Options:
    -d --detach       Run the resulting container in the background
    -s --site=NAME   Specify a site to run the shell on [default: primary]
  
  ENVIRONMENT may be an environment name or a path to an environment directory.
  Default: '.'