code: def ks_start_date(self):
      return ps.from_pandas(self.pd_start_date)
  
imports: import datetime
  import unittest
  import numpy
  import pandas
  from pyspark import pandas
  from pyspark.testing.pandasutils import PandasOnSparkTestCase
  from pyspark.testing.sqlutils import SQLTestUtils
label_desc: Use image node_id 3 for calling the SeriesDateTimeTestsMixin obj's underlying member method code with example usage: obj.ks_start_date() and returns: ps