bandmat problem when installing nnmnkwii v0.0.21 on python 3.8.2

I'm trying to run GMM-based voice conversion notebook.

When importing DTWAligner using from nnmnkwii.preprocessing.alignment import DTWAligner, I get the following error:

ModuleNotFoundError                       Traceback (most recent call last)
~/venv/tf/lib/python3.8/site-packages/nnmnkwii/paramgen/__init__.py in <module>
      4 try:
----> 5     import bandmat
      6 except ImportError:

ModuleNotFoundError: No module named 'bandmat'

During handling of the above exception, another exception occurred:

ImportError                               Traceback (most recent call last)
<ipython-input-10-e5e265211f3e> in <module>
----> 1 from nnmnkwii.preprocessing.alignment import DTWAligner

~/venv/tf/lib/python3.8/site-packages/nnmnkwii/preprocessing/alignment.py in <module>
      2 
      3 from nnmnkwii.preprocessing import trim_zeros_frames
----> 4 from nnmnkwii.baseline.gmm import MLPG
      5 
      6 from fastdtw import fastdtw

~/venv/tf/lib/python3.8/site-packages/nnmnkwii/baseline/gmm.py in <module>
      3 from sklearn.mixture.gaussian_mixture import _compute_precision_cholesky
      4 
----> 5 from nnmnkwii.paramgen import mlpg
      6 
      7 # TODO: this can be refactored to be more flexible

~/venv/tf/lib/python3.8/site-packages/nnmnkwii/paramgen/__init__.py in <module>
      5     import bandmat
      6 except ImportError:
----> 7     raise ImportError("""
      8     `bandmat` is required for the `paramgen` module but not found.
      9     Please install it manually by:

ImportError: 
    `bandmat` is required for the `paramgen` module but not found.
    Please install it manually by:
    `pip install bandmat`.
    If you see installation errors, please report to https://github.com/MattShannon/bandmat.

My python version: 3.8.2 Installed nnmnkwii version: 0.0.21

I can not install bandmat using pip because of the problem mentioned here.

On nnmnkwii change log, it is expressed that bandmat is optional for v0.0.19 as it causes problems during installation. Isn't it optional for v0.0.21 too? Should I compile bandmat from source or is there a solution to it?

r9y9 / nnmnkwii

bandmat problem when installing nnmnkwii v0.0.21 on python 3.8.2 #104