code: def test_expanding_count(self):
      self._test_expanding_func("count")
  
file_path: spark/python/pyspark/pandas/tests/window/test_expanding.py
imports: import numpy
  import pandas
  import pyspark.pandas
  from pyspark.testing.pandasutils import PandasOnSparkTestCase
label_desc: Use image node_id 2 for calling the ExpandingMixin obj's underlying member method code with example usage: obj.test_expanding_count() without return types