code: def disconnect_all(self):
          
          rhs = 'b:' + self.definition['node_class'].__label__
          rel = _rel_helper(lhs='a', rhs=rhs, ident='r', **self.definition)
          q = 'MATCH (a) WHERE id(a)={self} MATCH ' + rel + ' DELETE r'
          self.source.cypher(q)
docs: Disconnect all nodes
  
          :return: