docs: def read_pkl_and_pklz(filename):
      """
      Try read zipped or not zipped pickle file
      """
      fcontent = None
      try:
          import gzip
          f = gzip.open(filename, 'rb')
          fcontent = f.read()
          f.close()
      except IOError as e:
          # if the problem is in not gzip file
          logger.info("Input gzip exception: " + str(e))
          f = open(filename, 'rb')
          fcontent = f.read()
          f.close()
      except Exception as e:
          # other problem
          import traceback
          logger.error("Input gzip exception: " + str(e))
          logger.error(traceback.format_exc())
  
      return fcontent