code: def test_resample_calendar():
      df = to_dataframe(data)
      assert isinstance(resample(df, "W-Mon"), DataFrame)
      assert list(resample(df, "W-Mon").index.values[-2:]) == [
          numpy.datetime64("2019-05-06T00:00:00.000000000"),
          numpy.datetime64("2019-05-13T00:00:00.000000000"),
      ]
  
file_path: finta/tests/test_utils_unit.py
imports: import pytest
  import os
  from pandas import DataFrame, Series
  from finta import TA
  from finta.utils import to_dataframe, resample, trending_down, trending_up
  import numpy
  import json
label_desc: Use image node_id 4 for calling a global function with example usage: test_resample_calendar() without return types