code: def properties_flatten(in_list: Sequence) -> List:
      """Flatten a list of lists into a single level list."""
      out = []
      for el in in_list:
          if isinstance(el, Sequence) and not isinstance(
              el, (str, bytes)
          ):
              out.extend(el)
          else:
              out.append(el)
      return out
  
file_path: deepchecks/deepchecks/vision/utils/label_prediction_properties.py
imports: from typing import List, Sequence, Union
  import numpy
label_desc: Use image node_id 15 for calling a global function with example usage: properties_flatten(in_list) and returns: out