text: from igraph import Graph
  from parvusdb import GraphDatabase
  from .node_matcher import VectorNodeMatcher
  
  
  class DrsMatcher:
      def __init__(self, small_drs, metric):
          self.small_drs = small_drs
          self.metric = metric
  
      def visit(self, g):
          if not isinstance(g, Graph):
              raise TypeError("DrsRule.visit_to_graph() needs an igraph.Graph as an argument")
          db = GraphDatabase(g, node_matcher=VectorNodeMatcher(self.metric))
          rule = 'MATCH ' + str(self.small_drs) + ' RETURN __RESULT__;'
          lst = db.query(rule)
          return lst
  