docs: def up(force=True, env=None, **kwargs):
      "Starts a new experiment"
      inventory = os.path.join(os.getcwd(), "hosts")
      conf = Configuration.from_dictionnary(provider_conf)
      provider = Enos_vagrant(conf)
      roles, networks = provider.init()
      check_networks(roles, networks)
      env["roles"] = roles
      env["networks"] = networks