code: def publisher(self, value=None):
          
          if not (value is None):
              if (self.metadatatype == "native"):
                  self.metadata['publisher'] = value
              else:
                  self._publisher = value
          if (self.metadatatype == "native"):
              if 'publisher' in self.metadata:
                  return self.metadata['publisher']
              else:
                  return None
          else:
              return self._publisher
docs: No arguments: Get the document's publisher from metadata
             Argument: Set the document's publisher in metadata