code: def dump(self, name, filename):
          
          if not self.exists(name):
              raise DatabaseError('database %s does not exist!')
          log.info('dumping %s to %s' % (name, filename))
          self._run_cmd('pg_dump', '--verbose', '--blobs', '--format=custom',
                        '--file=%s' % filename, name)
docs: Saves the state of a database to a file.
  
          Parameters
          ----------
          name: str
              the database to be backed up.
          filename: str
              path to a file where database backup will be written.