I've installed version 0.18.2 of scikit-learn on my Mac using

```
pip uninstall scikit-learn
pip install scikit-learn==0.18.2

```

However, when I run

```
python
>>> import sklearn
>>> sklearn.__version__

```

I get 

```
'0.17'

```

Interestingly, this older version is still installed even after I uninstall scikit-learn. Could this have something to do with multiple versions of Python somehow being installed? I beat my head against the wall trying to use Anaconda at one point to try to get numpy and scipy running, and have since switched to ActivePython. When I run

```
which python

```

I get

```
/Library/Frameworks/Python.framework/Versions/2.7/bin/python

```

I know there are very similar questions on SO, but none of the posted solutions have worked.