code: def test_multiple_feature_descriptors():
      def sum_func(sig: np.ndarray) -> float:
          return sum(sig)
  
      mfd = MultipleFeatureDescriptors(
          functions=[sum_func, FuncWrapper(np.max), np.min],
          series_names=["EDA", "TMP"],
          windows=["5s", "7.5s"],
          strides="2.5s",
      )
  
      assert len(mfd.feature_descriptions) == 3 * 2 * 2
  
      series_names = [fd.series_name for fd in mfd.feature_descriptions]
      assert set(series_names) == set([tuple(["EDA"]), tuple(["TMP"])])
      assert sum([el == tuple(["EDA"]) for el in series_names]) == 3 * 2
      assert sum([el == tuple(["TMP"]) for el in series_names]) == 3 * 2
  
      windows = [fd.window for fd in mfd.feature_descriptions]
      assert set(windows) == set(
          [pd.Timedelta(seconds=5), pd.Timedelta(seconds=7.5)]
      )
      assert (
          sum([el == pd.Timedelta(seconds=5) for el in windows])
          == 3 * 2
      )
      assert (
          sum([el == pd.Timedelta(seconds=7.5) for el in windows])
          == 3 * 2
      )
  
      strides = flatten([fd.stride for fd in mfd.feature_descriptions])
      assert set(strides) == set([pd.Timedelta(seconds=2.5)])
  
      functions = [fd.function for fd in mfd.feature_descriptions]
      assert len(set(functions)) == 3
      output_names = [f.output_names for f in functions]
      assert all([len(outputs) == 1 for outputs in output_names])
      output_names = [outputs[0] for outputs in output_names]
      assert set(output_names) == set(["sum_func", "amax", "amin"])
      assert sum([el == "sum_func" for el in output_names]) == 2 * 2
      assert sum([el == "amax" for el in output_names]) == 2 * 2
      assert sum([el == "amin" for el in output_names]) == 2 * 2
  
file_path: tsflex/tests/test_features_feature_descriptor.py
imports: import numpy
  import pandas
  import pytest
  from tsflex.features import FeatureDescriptor, FuncWrapper, MultipleFeatureDescriptors
  from tsflex.utils.data import flatten
label_desc: Use image node_id 13 for calling a global function with example usage: test_multiple_feature_descriptors() and returns: sum