Doesn't seem to work with Python 3.13

[tprrt]

The following issue occurs with Python 3.13, but no issues occur with Python 3.11:

>>> import sentencepiece as spm
Traceback (most recent call last):
  File '<stdin>', line 1, in <module>
    import sentencepiece as spm
  File '/usr/lib/python3.13/site-packages/sentencepiece/__init__.py', line 10, in <module>
    from . import _sentencepiece
ImportError: cannot import name '_sentencepiece' from partially initialized module 'sentencepiece' (most likely due to a circular import) (/usr/lib/python3.13/site-packages/sentencepiece/__init__.py)
>>> exit()