我试图运行一个需要numpy模块的python脚本，当我尝试安装它时，它显示它已经存在，当我运行import numpy它时抛出错误ImportError: No module named numpy，任何指导什么是错的？

[username@machine build]$ pip install numpy

You are using pip version 7.1.0, however version 18.1 is available.

You should consider upgrading via the 'pip install --upgrade pip' command.

Requirement already satisfied (use --upgrade to upgrade): numpy in /usr/lib64/python2.6/site-packages

下面的命令显示未安装numpy

[username@machine build]$ python

Python 2.7.12 (default, Feb 22 2017, 20:16:44)

[GCC 4.4.7 20120313 (Red Hat 4.4.7-11)] on linux2

Type "help", "copyright", "credits" or "license" for more information.

>>> import sys

>>> print(sys.version)

2.7.12 (default, Feb 22 2017, 20:16:44)

[GCC 4.4.7 20120313 (Red Hat 4.4.7-11)]

>>> import numpy

Traceback (most recent call last):

File "<stdin>", line 1, in <module>

ImportError: No module named numpy