code: def get_hash(self, source_geo_def=None, target_geo_def=None, **kwargs):
          
          if source_geo_def is None:
              source_geo_def = self.source_geo_def
          if target_geo_def is None:
              target_geo_def = self.target_geo_def
          the_hash = source_geo_def.update_hash()
          target_geo_def.update_hash(the_hash)
          hash_dict(kwargs, the_hash)
          return the_hash.hexdigest()
docs: Get hash for the current resample with the given *kwargs*.