code: def is_in_valid_relative_index_types(x) -> bool:
      return isinstance(x, RELATIVE_INDEX_TYPES) or is_integer_index(x)
  
file_path: sktime/sktime/utils/validation/series.py
imports: from typing import Union
  import numpy
  import pandas
label_desc: Use image node_id 3 for calling a global function with example usage: is_in_valid_relative_index_types(x) and returns: unknown