模块安装但无法导入答案

【问题标题】：Module installs but cannot be imported模块安装但无法导入
【发布时间】：2018-01-01 05:58:00
【问题描述】：

我是 Python 新手，我正在尝试在 Mac 上运行 Python2 脚本，该脚本依赖于我已安装但根据脚本找不到的模块。为什么以下失败？

Home:Dev m$ python -V
Python 2.7.10
Home:Dev m$ sudo pip install coincurve==5.2.0 pysha3
Password:
The directory '/Users/m/Library/Caches/pip/http' or its parent directory is not owned by the current user and the cache has been disabled. Please check the permissions and owner of that directory. If executing pip with sudo, you may want sudo's -H flag.
The directory '/Users/m/Library/Caches/pip' or its parent directory is not owned by the current user and caching wheels has been disabled. check the permissions and owner of that directory. If executing pip with sudo, you may want sudo's -H flag.
Collecting coincurve==5.2.0
  Downloading coincurve-5.2.0-cp27-cp27m-macosx_10_6_intel.whl (157kB)
    100% |████████████████████████████████| 163kB 1.3MB/s 
Collecting pysha3
  Downloading pysha3-1.0.2.tar.gz (829kB)
    100% |████████████████████████████████| 829kB 692kB/s 
Requirement already satisfied: cffi>=1.3.0 in /usr/local/lib/python2.7/site-packages (from coincurve==5.2.0)
Requirement already satisfied: asn1crypto in /usr/local/lib/python2.7/site-packages (from coincurve==5.2.0)
Requirement already satisfied: pycparser in /usr/local/lib/python2.7/site-packages (from cffi>=1.3.0->coincurve==5.2.0)
Installing collected packages: coincurve, pysha3
  Running setup.py install for pysha3 ... done
Successfully installed coincurve-5.2.0 pysha3-1.0.2
Home:Dev m$ pip show coincurve
Name: coincurve
Version: 5.2.0
Summary: Cross-platform Python CFFI bindings for libsecp256k1
Home-page: https://github.com/ofek/coincurve
Author: Ofek Lev
Author-email: ofekmeister@gmail.com
License: MIT/Apache-2.0
Location: /usr/local/lib/python2.7/site-packages
Requires: cffi, asn1crypto
Home:Dev m$ python
Python 2.7.10 (default, Jul 15 2017, 17:16:57) 
[GCC 4.2.1 Compatible Apple LLVM 9.0.0 (clang-900.0.31)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import coincurve
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ImportError: No module named coincurve
>>>

【问题讨论】：

你确定你在python2 shell中吗？在某些 Linux 发行版中，您必须将 python 版本指定为 python2 才能进入其 shell。
你是对的。正确答案是以python2 开头。你想把它作为一个答案，我会把它标记为正确吗？谢谢。
我刚刚做到了。

标签： python python-2.7

【解决方案1】：

问题是您实际上不在 python 2.7 shell 中。在某些 Linux 发行版中，您必须指定 python 版本才能进入其 shell。所以你运行以下命令：

python2

代替：

python

因为上面的命令会自动打开python 3.x shell。

【讨论】：