code: def check_isis_version(major, minor=0, patch=0):
      
      if ISIS_VERSION and (major, minor, patch) <= ISIS_VERISON_TUPLE:
          return
  
      msg = 'Version %s.%s.%s of isis required (%s found).'
      raise VersionError(msg % (major, minor, patch, ISIS_VERSION))
docs: Checks that the current isis version is equal to or above the suplied
      version.