code: def test_node_joinsource(tmpdir):
      """Test setting the joinsource to a Node."""
      tmpdir.chdir()
  
      # the iterated input node
      inputspec = pe.Node(
          IdentityInterface(fields=["n"]), name="inputspec"
      )
      inputspec.iterables = [("n", [1, 2])]
      # the join node
      join = pe.JoinNode(
          SetInterface(),
          joinsource=inputspec,
          joinfield="input1",
          name="join",
      )
  
      # the joinsource is the inputspec name
      assert (
          join.joinsource == inputspec.name
      ), "The joinsource is not set to the node name."
  
imports: import pytest
  from ....None import config
  from ...None import engine
  from ....interfaces import base
  from ....interfaces.utility import IdentityInterface, Function, Merge
  from ....interfaces.base import traits, File
label_desc: Use image node_id 2 for calling a global function with example usage: test_node_joinsource(tmpdir) without return types