Python 订单是否由'报告；系统路径'；搜索包的顺序？

Python

sys.path

中条目出现的顺序是否与包的查找顺序相对应？比如我有

>>> from pprint import pprint     
>>> pprint(sys.path)
['',
 '/Library/Python/2.7/site-packages/ipython-0.14.dev-py2.7.egg',
 '/Library/Python/2.7/site-packages/matplotlib-1.3.x-py2.7-macosx-10.8-intel.egg',
 '/Library/Python/2.7/site-packages/numpy-1.8.0.dev_3abd869_20121222-py2.7-macosx-10.8-intel.egg',
 '/Library/Python/2.7/site-packages/pymc-2.2-py2.7-macosx-10.8-intel.egg',
 '/Library/Python/2.7/site-packages/scikit_learn-0.13_git-py2.7-macosx-10.8-intel.egg',
 '/Library/Python/2.7/site-packages/scipy-0.12.0.dev_d631749_20121222-py2.7-macosx-10.8-intel.egg',
 '/Library/Python/2.7/site-packages/statsmodels-0.5.0-py2.7-macosx-10.8-intel.egg',
 '/Library/Python/2.7/site-packages/readline-6.2.4.1-py2.7-macosx-10.7-intel.egg',
 '/Library/Python/2.7/site-packages/nose-1.2.1-py2.7.egg',
 '/Library/Python/2.7/site-packages/six-1.2.0-py2.7.egg',
 '/Library/Python/2.7/site-packages/tornado-2.4.1-py2.7.egg',
 '/Library/Python/2.7/site-packages/pyzmq-2.2.0.1-py2.7-macosx-10.8-intel.egg',
 '/Library/Python/2.7/site-packages/patsy-0.1.0-py2.7.egg',
 '/Library/Python/2.7/site-packages/pip-1.2.1-py2.7.egg',
 '/Library/Python/2.7/site-packages/xattr-0.6.4-py2.7-macosx-10.8-intel.egg',
 '/Library/Python/2.7/site-packages/distribute-0.6.28-py2.7.egg',
 '/Library/Python/2.7/site-packages/astropy-0.3.dev2837-py2.7-macosx-10.8-intel.egg',
 '/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python27.zip',
 '/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7',
 '/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/plat-darwin',
 '/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/plat-mac',
 '/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/plat-mac/lib-scriptpackages',
 '/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python',
 '/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-tk',
 '/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-old',
 '/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-dynload',
 '/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/PyObjC',
 '/Library/Python/2.7/site-packages']

所以，总的来说，我有

['',
 '/Library/Python/2.7/site-packages/PKG_WITH_EGG.egg',
 ...
 '/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python',
 ...
 '/Library/Python/2.7/site-packages']

---

这是否意味着，如果我安装的软件包（在“站点软件包”中）碰巧有一个

.egg

，它将取代可能在“Extras”中的同一软件包的一个版本，但那些（在“站点软件包”中）没有

.egg

的软件包将被“Extras”中的任何版本取代，模块通常是按这个顺序搜索的，但子模块是在基本模块树中搜索的。@Keith：那么，如果我有一个模块在“Extras”和“site packages”中，那么“site packages”版本只有在它恰好是鸡蛋的形式时才会被使用？（如果是的话，我想这意味着你是。）不是鸡蛋、包裹或模块。鸡蛋是在sys.path中搜索模块的容器（子目录或zip文件）。site packages是搜索模块或包的目录。包是一个目录，其中有一个

\uuuu init\uuuu.py

文件。@Keith:我不确定我是否明白。如果我有，在“Extras”中说

somepkg YY

，并且（1）

somepkg

（或者

somepkg XX.egg info

）在“site packages”中是否加载了版本“YY”；（2） 如果我在“site packages”（随后似乎被添加到“sys.path”）中有

somepkg XX.egg

，那么版本“XX”是否已加载？Python解释器不会搜索egg信息，Python也不会搜索.egg目录，除非它位于sys.path中。你可以用我的工具告诉你它找到了哪一个。