code: def is_compatible(self, model, version):
          
          if not model in self.models:
              return False
          if self.max_ykver:
              return (version >= self.min_ykver and
                      version <= self.max_ykver)
          else:
              return version >= self.min_ykver
docs: Check if this flag is compatible with a YubiKey of version 'ver'.