code: def test_get_ivs_custom(self):
      scale_custom = {"eta1": "y2", "eta2": "y5", "xi1": "x1"}
  
      self.assertSetEqual(
          self.custom.get_ivs(
              "xi1", "x2", scaling_indicators=scale_custom
          ),
          {"y1", "y2", "y3", "y4", "y5"},
      )
      self.assertSetEqual(
          self.custom.get_ivs(
              "xi1", "y4", scaling_indicators=scale_custom
          ),
          {"x2"},
      )
      self.assertSetEqual(
          self.custom.get_ivs(
              "xi1", "y1", scaling_indicators=scale_custom
          ),
          {"x2", "y4"},
      )
      self.assertSetEqual(
          self.custom.get_ivs(
              "xi1", "eta1", scaling_indicators=scale_custom
          ),
          {"x2", "y4"},
      )
      # TODO: Test this and fix.
      self.assertSetEqual(
          self.custom.get_ivs(
              "y1", "eta1", scaling_indicators=scale_custom
          ),
          {"x2", "y4", "y5"},
      )
      self.assertSetEqual(
          self.custom.get_ivs(
              "y1", "eta2", scaling_indicators=scale_custom
          ),
          {"x1", "x2", "y2", "y3", "y4"},
      )
      self.assertSetEqual(
          self.custom.get_ivs(
              "y4", "y1", scaling_indicators=scale_custom
          ),
          set(),
      )
      self.assertSetEqual(
          self.custom.get_ivs(
              "eta1", "y3", scaling_indicators=scale_custom
          ),
          {"x1", "x2", "y4"},
      )
  
imports: import os
  import unittest
  import networkx
  import numpy
  import numpy.testing
  from pgmpy.models import SEM, SEMAlg, SEMGraph
label_desc: Use image node_id 17 for calling the TestSEMGraph obj's underlying member method code with example usage: obj.test_get_ivs_custom() without return types