code: def test_loc_on_numpy_datetimes(self):
      pdf = pd.DataFrame(
          {"x": [1, 2, 3]},
          index=list(map(np.datetime64, ["2014", "2015", "2016"])),
      )
      psdf = ps.from_pandas(pdf)
  
      self.assert_eq(psdf.loc["2014":"2015"], pdf.loc["2014":"2015"])
  
imports: 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 10 for calling the IndexingLocMixin obj's underlying member method code with example usage: obj.test_loc_on_numpy_datetimes() without return types