code: def dtype(cls, dataset, dimension):
      return dataset.data.dtype
  
imports: import numpy
  from ..None import util
  from ..dimension import dimension_name
  from ..element import Element
  from ..ndmapping import NdMapping, item_check, sorted_context
  from .interface import DataError, Interface
label_desc: Use image node_id 6 for calling the ArrayInterface obj's underlying member method code with example usage: obj.dtype(cls, dataset, dimension) and returns: dataset