docstr: adding edges again should update the edges origin attr
docstr_tok: ["adding","edges","again","should","update","the","edges","origin","attr"]
code: def test_add_edges_from_multiple_times(self):
      """adding edges again should update the edges origin attr"""
  
      sm = StructureModel()
      edges = [(1, 2), (2, 3)]
      sm.add_edges_from(edges, "unknown")
      assert all(
          (u, v, "unknown") in sm.edges.data("origin") for u, v in edges
      )
      sm.add_edges_from(edges, "learned")
      assert all(
          (u, v, "learned") in sm.edges.data("origin") for u, v in edges
      )
  
imports: import pytest
  from networkx.exception import NodeNotFound
  from causalnex.structure import StructureModel
label_desc: Use image node_id 7 for calling the TestStructureModelAddEdgesFrom obj's underlying member method code with example usage: obj.test_add_edges_from_multiple_times() without return types