docs: def _is_numeric_data(ll):
      """
      List of lists of csv values data
      :param list ll:
      :return bool: True, all lists are numeric lists, False, data contains at least one numeric list.
      """
      for l in ll:
          try:
              if any(math.isnan(float(i)) or isinstance(i, str) for i in l):
                  return False
              # if not all(isinstance(i, (int, float)) or math.isnan(float(i)) for i in l):
              #     # There is an entry that is a non-numeric entry in this list
              #     return False
          except ValueError:
              # Trying to case a str as a float didnt work, and we got an error
              return False
      # All arrays are 100% numeric or "nan" entries.
      return True