code: def assert_edges_unique_in(self, es):
      pairs = sorted(e.tuple for e in es)
      self.assertEqual(pairs, sorted(set(pairs)))
  
imports: import unittest
  from igraph import Graph, Edge, EdgeSeq, VertexSeq
  from .utils import is_pypy
label_desc: Use image node_id 1 for calling the EdgeSeqTests obj's underlying member method code with example usage: obj.assert_edges_unique_in(es) without return types