poetry run pytest and module not found

還沒有人認領這個 Issue。

`poetry run pytest`

==================================================================== test session starts ====================================================================
platform linux -- Python 3.8.1, pytest-5.3.5, py-1.8.1, pluggy-0.13.1
benchmark: 3.2.3 (defaults: timer=time.perf_counter disable_gc=False min_rounds=5 min_time=0.000005 max_time=1.0 calibration_precision=10 warmup=False warmup_iterations=100000)
rootdir: /home/frag/linfa-python
plugins: benchmark-3.2.3, asyncio-0.10.0
collected 0 items / 1 error

========================================================================== ERRORS ===========================================================================
__________________________________________________________ ERROR collecting tests/test_k_means.py ___________________________________________________________
ImportError while importing test module '/home/frag/linfa-python/tests/test_k_means.py'.
Hint: make sure your test modules/packages have valid Python names.
Traceback:
tests/test_k_means.py:5: in
from linfa import KMeans
linfa/__init__.py:1: in
from .LinfaKMeans import KMeans, WrappedKMeans
linfa/LinfaKMeans.py:6: in
from .linfa import WrappedKMeans
E ModuleNotFoundError: No module named 'linfa.linfa'

`rustc -V`
rustc 1.40.0-nightly (0e8a4b441 2019-10-16)

`uname -a`
Linux amx-dev-lap 5.3.0-7629-generic #31~1581628825~19.10~f90b7d5-Ubuntu SMP Fri Feb 14 19:56:45 UTC x86_64 x86_64 x86_64 GNU/Linux

從 tests/test_k_means.py 開始，沿著 linfa/__init__.py 和 linfa/LinfaKMeans.py 追蹤 import。執行 poetry run pytest，並檢查缺少的 linfa.linfa 模組是如何產生或公開的；當測試收集能夠在沒有 ModuleNotFoundError 的情況下繼續時，即表示完成。

由索引模型根據 Issue 內容生成。