docs: def int_global_to_local(self, index, axis=0):
          """ Calculate local index from global index for integer input
  
          :param index: global index as integer
          :param axis: current axis to process
          :return:
          """
  
          # Warum >= an dieser Stelle. Eigentlich sollte > ausreichend sein! Test!
          if index >= self.__mask[axis].stop-self.__halos[1][axis]:
              return None
  
          if index < self.__mask[axis].start+self.__halos[0][axis]:
              return None
  
          return index-self.__mask[axis].start