code: def get_datatype(self, propid):
          
          if _debug: Object._debug("get_datatype %r", propid)
  
          # get the property
          prop = self._properties.get(propid)
          if not prop:
              raise PropertyError(propid)
  
          # return the datatype
          return prop.datatype
docs: Return the datatype for the property of an object.