code: def test_parameter_checking(self):
      g = create_test_graph(self_loop=True)
  
      graph_schema = g.create_graph_schema()
      bfw = SampledHeterogeneousBreadthFirstWalk(g, graph_schema)
  
      nodes = [0, 1]
      n = 1
      n_size = [1]
      seed = 1001
  
      with pytest.raises(ValueError):
          # nodes should be a list of node ids even for a single node
          bfw.run(nodes=None, n=n, n_size=n_size, seed=seed)
      with pytest.raises(ValueError):
          bfw.run(nodes=0, n=n, n_size=n_size, seed=seed)
      # n has to be positive integer
      with pytest.raises(ValueError):
          bfw.run(nodes=nodes, n=-1, n_size=n_size, seed=seed)
      with pytest.raises(ValueError):
          bfw.run(nodes=nodes, n=10.1, n_size=n_size, seed=seed)
      with pytest.raises(ValueError):
          bfw.run(nodes=nodes, n=0, n_size=n_size, seed=seed)
          # n_size has to be list of positive integers
      with pytest.raises(ValueError):
          bfw.run(nodes=nodes, n=n, n_size=0, seed=seed)
      with pytest.raises(ValueError):
          bfw.run(nodes=nodes, n=n, n_size=[-5], seed=seed)
      with pytest.raises(ValueError):
          bfw.run(nodes=nodes, n=-1, n_size=[2.4], seed=seed)
      with pytest.raises(ValueError):
          bfw.run(nodes=nodes, n=n, n_size=(1, 2), seed=seed)
          # graph_schema must be None or GraphSchema type
      with pytest.raises(ValueError):
          SampledHeterogeneousBreadthFirstWalk(
              g, graph_schema="graph schema"
          )
  
      with pytest.raises(ValueError):
          SampledHeterogeneousBreadthFirstWalk(g, graph_schema=9092)
  
      with pytest.raises(ValueError):
          bfw.run(nodes=nodes, n=n, n_size=n_size, seed=-1235)
      with pytest.raises(ValueError):
          bfw.run(nodes=nodes, n=n, n_size=n_size, seed=10.987665)
      with pytest.raises(ValueError):
          bfw.run(nodes=nodes, n=n, n_size=n_size, seed=-982.4746)
      with pytest.raises(ValueError):
          bfw.run(
              nodes=nodes, n=n, n_size=n_size, seed="don't be random"
          )
  
      # If no root nodes are given, an empty list is returned which is not an error but I thought this method
      # is the best for checking this behaviour.
      nodes = []
      subgraph = bfw.run(nodes=nodes, n=n, n_size=n_size, seed=seed)
      assert len(subgraph) == 0
  
file_path: stellargraph/tests/data/test_heterogeneous_breadth_first_walker.py
imports: import pandas
  import numpy
  import pytest
  from stellargraph.data.explorer import SampledHeterogeneousBreadthFirstWalk
  from stellargraph.core.graph import StellarGraph
  from ..test_utils.graphs import example_graph_random
label_desc: Use image node_id 1 for calling the TestSampledHeterogeneousBreadthFirstWalk obj's underlying member method code with example usage: obj.test_parameter_checking() without return types