Python无法找到与pip一起安装的软件包

Question

在Mac上，尝试获取Python 3.6安装程序。

Sams-MacBook-Pro:~ samgreenberg$ which pip3 
/Library/Frameworks/Python.framework/Versions/3.6/bin/pip3 
Sams-MacBook-Pro:~ samgreenberg$ which python3 
/Library/Frameworks/Python.framework/Versions/3.6/bin/python3 

然后

Sams-MacBook-Pro:~ samgreenberg$ pip3 list 
DEPRECATION: The default format will switch to columns in the future. 

You can use --format=(legacy|columns) (or define a format=(legacy|columns) in your pip.conf under the [list] section) to disable this warning. 
biopython (1.70) 
certifi (2017.7.27.1) 
chardet (3.0.4) 
cycler (0.10.0) 
decorator (4.1.2) 
idna (2.6) 
ipython-genutils (0.2.0) 
jsonschema (2.6.0) 
jupyter-core (4.3.0) 
matplotlib (2.0.2) 
nbformat (4.4.0) 
numpy (1.13.1) 
olefile (0.44) 
Pillow (4.3.0) 
pip (9.0.1) 
plotly (2.0.15) 
pyparsing (2.2.0) 
python-dateutil (2.6.1) 
pytz (2017.2) 
requests (2.18.4) 
setuptools (28.8.0) 
six (1.10.0) 
traitlets (4.3.2) 
urllib3 (1.22) 

所以biopython似乎安装

Sams-MacBook-Pro:~ samgreenberg$ python3 -m pip install biopython 
Requirement already satisfied: biopython in /Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages 
Requirement already satisfied: numpy in /Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages (from biopython) 

肯定安装。

Sams-MacBook-Pro:~ samgreenberg$ python3 
Python 3.6.2 (v3.6.2:5fd33b5926, Jul 16 2017, 20:11:06) 
[GCC 4.2.1 (Apple Inc. build 5666) (dot 3)] on darwin 
Type "help", "copyright", "credits" or "license" for more information. 
>>> import urllib3 
>>> import biopython 
Traceback (most recent call last): 
    File "<stdin>", line 1, in <module> 
ModuleNotFoundError: No module named 'biopython' 
>>> 

urllib3工作，但不是新安装的软件包。使用pip卸载并重新安装没有效果，当我尝试使用随机的其他软件包时，结果相同。我究竟做错了什么？我对Python或OSX没有特别的经验。我的电脑预装了Python 2.7，但我很小心地在命令中使用Python3。

Answer 1

当我们使用一些python模块时，我们通常会写>>> import module。例如，>>> import urllib3。但是，一些软件包，包括biopython，不在这个规则之内。您尝试键入>>> import Bio和>>> print(Bio.__version__)。请在http://biopython.org/DIST/docs/tutorial/Tutorial.html查询更多详情。

--original answer--

请尝试键入以下脚本：

>>import sys 
>>print(sys.path) 

我觉得有没有/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages但只有python2的模块路径。

如果要解决这个问题暂时的，请使用以下命令：

>>sys.path.append("/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages") 

请~/.bash_profile定义PYTHONPATH并重新启动你的终端，如果你总是使用python3：

PYTHONPATH=/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages:$PYTHONPATH