Error: No module named 'option_parser'

[Ishihara-Masabumi]

When I run the following command line, the following error occurred.

$ python3 datasets/split_joint.pyTraceback (most recent call last):
  File "datasets/split_joint.py", line 10, in <module>
    from option_parser import try_mkdir
ModuleNotFoundError: No module named 'option_parser'

Please let me know how to fix it.