class_docstr: General PySpark tests that depend on scipy
code: def test_serialize(self):
      from scipy.special import gammaln
  
      x = range(1, 5)
      expected = list(map(gammaln, x))
      observed = self.sc.parallelize(x).map(gammaln).collect()
      self.assertEqual(expected, observed)
  
imports: import math
  import sys
  import unittest
  from pyspark import serializers
  from pyspark.serializers import CloudPickleSerializer, CompressedSerializer, AutoBatchedSerializer, BatchedSerializer, AutoSerializer, NoOpSerializer, PairDeserializer, FlattenedValuesSerializer, CartesianDeserializer, CPickleSerializer, UTF8Deserializer, MarshalSerializer
  from pyspark.testing.utils import PySparkTestCase, read_int, write_int, ByteArrayOutput, have_numpy, have_scipy
label_desc: Use image node_id 1 for calling the SciPyTests obj's underlying member method code with example usage: obj.test_serialize() without return types