code: def test_hasnans(self):
      # BooleanType
      pser = pd.Series([True, False, True, True])
      psser = ps.from_pandas(pser)
      self.assert_eq(pser.hasnans, psser.hasnans)
  
      pser = pd.Series([True, False, np.nan, True])
      psser = ps.from_pandas(pser)
      self.assert_eq(pser.hasnans, psser.hasnans)
  
      # TimestampType
      pser = pd.Series([pd.Timestamp("2020-07-30") for _ in range(3)])
      psser = ps.from_pandas(pser)
      self.assert_eq(pser.hasnans, psser.hasnans)
  
      pser = pd.Series(
          [
              pd.Timestamp("2020-07-30"),
              np.nan,
              pd.Timestamp("2020-07-30"),
          ]
      )
      psser = ps.from_pandas(pser)
      self.assert_eq(pser.hasnans, psser.hasnans)
  
      # DecimalType
      pser = pd.Series([Decimal("0.1"), Decimal("NaN")])
      psser = ps.from_pandas(pser)
      self.assert_eq(pser.hasnans, psser.hasnans)
  
      # empty
      pser = pd.Series([])
      psser = ps.from_pandas(pser)
      self.assert_eq(pser.hasnans, psser.hasnans)
  
imports: import unittest
  from decimal import Decimal
  import numpy
  import pandas
  from pyspark import pandas
  from pyspark.testing.pandasutils import ComparisonTestBase
  from pyspark.testing.sqlutils import SQLTestUtils
label_desc: Use image node_id 18 for calling the SeriesStatMixin obj's underlying member method code with example usage: obj.test_hasnans() without return types