code: def test_get_node_nsamples(spark_dtree):
      assert (
          spark_dtree.get_node_nsamples(0) == 891
      ), "Node samples for node 0 should be 891"
      assert (
          spark_dtree.get_node_nsamples(1) == 577
      ), "Node samples for node 1 should be 577"
      assert (
          spark_dtree.get_node_nsamples(5) == 559
      ), "Node samples for node 5 should be 559"
      assert (
          spark_dtree.get_node_nsamples(8) == 3
      ), "Node samples for node 3 should be 3"
      assert (
          spark_dtree.get_node_nsamples(12) == 144
      ), "Node samples for node 12 should be 144"
      assert (
          spark_dtree.get_node_nsamples(10) == 2
      ), "Node samples node node 10 should be 2"
      assert (
          spark_dtree.get_node_nsamples(16) == 23
      ), "Node samples for node 16 should be 23"
  
imports: import numpy
  import pyspark
  import pytest
  from pyspark.ml.classification import DecisionTreeClassificationModel
  from pyspark.sql import SparkSession
  from dtreeviz.models.spark_decision_tree import ShadowSparkTree
label_desc: Use image node_id 7 for calling a global function with example usage: test_get_node_nsamples(spark_dtree) without return types