docs: def set_data(self, data):
          """Sets the content data.
  
          arg:    data (osid.transport.DataInputStream): the content data
          raise:  InvalidArgument - ``data`` is invalid
          raise:  NoAccess - ``Metadata.isReadOnly()`` is ``true``
          raise:  NullArgument - ``data`` is ``null``
          *compliance: mandatory -- This method must be implemented.*
  
          """
          if data is None:
              raise errors.NullArgument('data cannot be None')
          if not isinstance(data, DataInputStream):
              raise errors.InvalidArgument('data must be instance of DataInputStream')
          dbase = JSONClientValidated('repository',
                                      runtime=self._runtime).raw()
          filesys = gridfs.GridFS(dbase)
          self._my_map['data'] = filesys.put(data._my_data)
          data._my_data.seek(0)
          self._my_map['base64'] = base64.b64encode(data._my_data.read())