1）调用python 2.7
简而言之：不要这样做。将该路径称为“ / usr / lib / python * 2.6 * / site-packages /”的原因有很多。
原因之一是，通常在此目录中存储“已编译”的python文件（.pyc）。python 2.6和python 2.7 .pyc文件不兼容：
$ python2.7 /usr/lib/python2.6/sitecustomize.pycRuntimeError: Bad magic number in .pyc file
python会跳过它无法理解的pyc文件，但是您至少会失去预编译文件的好处。
另一个原因是，事情可能会混淆：
$ strace -f python2.7 /usr/lib/python2.6/sitecustomize.py...stat("/etc/python2.6", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0stat("/etc/python2.6", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0stat("/etc/python2.6/apport_python_hook", 0x7fffa15601f0) = -1 ENOENT (No such file or directory)open("/etc/python2.6/apport_python_hook.so", O_RDONLY) = -1 ENOENT (No such file or directory)open("/etc/python2.6/apport_python_hookmodule.so", O_RDONLY) = -1 ENOENT (No such file or directory)open("/etc/python2.6/apport_python_hook.py", O_RDONLY) = -1 ENOENT (No such file or directory)open("/etc/python2.6/apport_python_hook.pyc", O_RDONLY) = -1 ENOENT (No such file or directory)stat("/usr/lib/python2.7/apport_python_hook", 0x7fffa15601f0) = -1 ENOENT (No such file or directory)open("/usr/lib/python2.7/apport_python_hook.so", O_RDONLY) = -1 ENOENT (No such file or directory)open("/usr/lib/python2.7/apport_python_hookmodule.so", O_RDONLY) = -1 ENOENT (No such file or directory)open("/usr/lib/python2.7/apport_python_hook.py", O_RDONLY) = -1 ENOENT (No such file or directory)open("/usr/lib/python2.7/apport_python_hook.pyc", O_RDONLY) = -1 ENOENT (No such file or directory)stat("/usr/lib/python2.7/plat-linux2/apport_python_hook", 0x7fffa15601f0) = -1 ENOENT (No such file or directory)...在您的情况下，我会在python2.7目录中安装python 2.7所需的模块。
2）调用python 2.6
您可能需要看一下手册页中描述PYTHONHOME的部分：
PYTHONHOME：更改标准Python库的位置。默认情况下，在$ {prefix} / lib / python [version]和$
{exec_prefix} / lib / python [version]中搜索这些库，其中$ {prefix}和$
{exec_prefix}是与安装有关的目录，默认情况下到/ usr / local
您可以将python
2.7特定文件/模块存储在本地安装中的相应目录中。仅当您运行特定版本的python时，才会选择这些文件/模块。在这种情况下，您不得设置PYTHONPATH（或PYTHONHOME）。
注意：这正是Debian（可能还有其他发行版）管理同时安装的不同python版本的方式。
[编辑：在收到niboshi的评论后，添加了第1节。]
