[Bug] Using spleeter separate on Windows 10 fails, exception related to Numba core

Description

Installed Spleeter on Win 10 x64 with pip through latest Anaconda version - 2020.02.

Running “spleeter separate” fails, throws exception saying DLL load failed, tracing to Numba error (tried with both python 3.7 and 3.6 environments).

Step to reproduce

1. Install using pip install spleeter in Anaconda
2. Run any separate command
3. Error

Output

spleeter separate -i split.mp3 -o audio_output
Traceback (most recent call last):
  File "c:\users\kassym\.conda\envs\snakes\lib\site-packages\numba\core\typeconv\typeconv.py", line 4, in <module>
    from numba.core.typeconv import _typeconv
ImportError: DLL load failed: The specified module could not be found.

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "c:\users\kassym\.conda\envs\snakes\lib\runpy.py", line 193, in _run_module_as_main
    "__main__", mod_spec)
  File "c:\users\kassym\.conda\envs\snakes\lib\runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "C:\Users\Kassym\.conda\envs\snakes\Scripts\spleeter.exe\__main__.py", line 7, in <module>
  File "c:\users\kassym\.conda\envs\snakes\lib\site-packages\spleeter\__main__.py", line 54, in entrypoint
    main(sys.argv)
  File "c:\users\kassym\.conda\envs\snakes\lib\site-packages\spleeter\__main__.py", line 40, in main
    from .commands.separate import entrypoint
  File "c:\users\kassym\.conda\envs\snakes\lib\site-packages\spleeter\commands\separate.py", line 15, in <module>
    from ..separator import Separator
  File "c:\users\kassym\.conda\envs\snakes\lib\site-packages\spleeter\separator.py", line 23, in <module>
    from librosa.core import stft, istft
  File "c:\users\kassym\.conda\envs\snakes\lib\site-packages\librosa\__init__.py", line 12, in <module>
    from . import core
  File "c:\users\kassym\.conda\envs\snakes\lib\site-packages\librosa\core\__init__.py", line 125, in <module>
    from .time_frequency import *  # pylint: disable=wildcard-import
  File "c:\users\kassym\.conda\envs\snakes\lib\site-packages\librosa\core\time_frequency.py", line 11, in <module>
    from ..util.exceptions import ParameterError
  File "c:\users\kassym\.conda\envs\snakes\lib\site-packages\librosa\util\__init__.py", line 77, in <module>
    from .utils import *  # pylint: disable=wildcard-import
  File "c:\users\kassym\.conda\envs\snakes\lib\site-packages\librosa\util\utils.py", line 10, in <module>
    import numba
  File "c:\users\kassym\.conda\envs\snakes\lib\site-packages\numba\__init__.py", line 20, in <module>
    from numba.misc.special import (
  File "c:\users\kassym\.conda\envs\snakes\lib\site-packages\numba\misc\special.py", line 3, in <module>
    from numba.core.typing.typeof import typeof
  File "c:\users\kassym\.conda\envs\snakes\lib\site-packages\numba\core\typing\__init__.py", line 1, in <module>
    from .context import BaseContext, Context
  File "c:\users\kassym\.conda\envs\snakes\lib\site-packages\numba\core\typing\context.py", line 11, in <module>
    from numba.core.typeconv import Conversion, rules
  File "c:\users\kassym\.conda\envs\snakes\lib\site-packages\numba\core\typeconv\rules.py", line 2, in <module>
    from .typeconv import TypeManager, TypeCastingRules
  File "c:\users\kassym\.conda\envs\snakes\lib\site-packages\numba\core\typeconv\typeconv.py", line 17, in <module>
    raise ImportError(msg % (url, reportme, str(e), sys.executable))
ImportError: Numba could not be imported.
If you are seeing this message and are undertaking Numba development work, you may need to re-run:

python setup.py build_ext --inplace

(Also, please check the development set up guide http://numba.pydata.org/numba-doc/latest/developer/contributing.html.)

If you are not working on Numba development:

Please report the error message and traceback, along with a minimal reproducer
at: https://github.com/numba/numba/issues/new

If more help is needed please feel free to speak to the Numba core developers
directly at: https://gitter.im/numba/numba

Thanks in advance for your help in improving Numba!

The original error was: 'DLL load failed: The specified module could not be found.'
--------------------------------------------------------------------------------
If possible please include the following in your error report:

sys.executable: c:\users\kassym\.conda\envs\snakes\python.exe

Environment

OS	Windows 10 x64
Installation type	pip
RAM available	16GB
Hardware spec	Intel Core i7-8750H / GTX 1070

Additional context

Standard steps taken on a clean machine - just downloaded and installed anaconda, there were no previous installations of python, anaconda, or spleeter.

[mmoussallam]

Hi @kass-kass @yoomy3 @desoconner

This seem to be quite an odd behavior linked to some version of numba on windows: https://github.com/numba/numba/issues/4732

I can only encourage you to manually force a pip install numba==0.45.0 as suggested as it seems to solve the issue (can’t reproduce it myself)

[dankwartrustow]

This fixed the exact issue for me as well on Windows 10.