old_contents: def includeme(config):
      # look into following modules' includeme function
      # in order to register routes
      config.include(__name__ + '.network')
      config.include(__name__ + '.system')
      config.include(__name__ + '.lvm')
      config.include(__name__ + '.block')
      config.include(__name__ + '.fs')
      config.include(__name__ + '.utilities')
      config.scan()             # scan to register view callables, must be last statement
new_contents: def includeme(config):
      # look into following modules' includeme function
      # in order to register routes
      config.include(__name__ + '.network')
      config.include(__name__ + '.system')
      config.include(__name__ + '.lvm')
      config.include(__name__ + '.block')
      config.include(__name__ + '.fs')
      config.include(__name__ + '.utils')
      config.scan()             # scan to register view callables, must be last statement
subject: fix a bug