sklearn模块不能与py.test一起使用

Question

我有scikit版本0.18.1。没有py.test，如果我在我的终端上运行它，它工作正常。没有这样的错误。

我正在尝试导入model_selection，但py.test给出了以下错误：

==================================== ERRORS ====================================
_________________________ ERROR collecting test_knn.py _________________________
test_knn.py:14: in <module>
    from knn import knn
knn.py:2: in <module>
    from sklearn.model_selection import cross_val_score
E   ImportError: No module named 'sklearn.model_selection'
=========================== 1 error in 1.63 seconds ============================

以下是我的.travis.yml

language: python
python:
  - "2.7"
  - "3.4"
  - "3.5"
# command to install dependencies
install:
  - pip install -r requirements.txt
# command to run tests
script: py.test