lxml

When used carefully , lxml can provide all three .

然而，如果得到合理使用，lxml可以满足全部三个要求。

The lxml parse method reads the entire document and builds an in-memory tree .

lxmlparse方法读取整个文档并在内存中构建一个树。

In addition to the use of specific methods within lxml , you can use approaches outside of the library to influence execution speed .

除了使用lxml内部的特定方法外，还可以通过库以外的方法提高执行速度。

Consult the FAQ section on threads in the lxml documentation for more information .

要了解更多内容，可参考lxml文档中有关线程的FAQ部分。

Which parts of lxml you use in your code depends on your needs : Are you comfortable with XPath ?

您要在代码中使用lxml的哪一部分取决于您的需求：您是否熟悉XPath？

This article does not cover all of lxml but instead demonstrates techniques to efficiently process very large XML files , optimizing for high speed and low memory usage .

本文并没有介绍lxml的所有部分，但是演示了一些可以有效处理大型XML文件、进行优化以提高处理速度并减少内存使用的技术。

Object models such as lxml 's objectify or Amara might be more natural for Python developers when speed is not a consideration .

如果不需要考虑速度的话，lxml的对象化或Amara等对象模型对于Python开发人员来说可能更自然。

One effect of this is that a node in lxml can have one and only one parent . ( cElementTree has no concept of parent nodes . )

该特性的一个特点就是lxml中的节点有且仅有一个父节点（cElementTree没有父节点）。

Lxml supplies two other options for discovering subnodes : the iterchildren / iterdescendants methods and true XPath .

lxml提供了另外两种查找子节点的选项：iterchildren/iterdescendants方法和真正的XPath。

Typical gains for a pure Python program are between two and four times , but lxml does most of its work in C , so the difference is unusually small .

一个纯Python程序的典型性能收益是普通程序的2至4倍，但是lxml使用C语言完成了大部分工作，因此它们之间的差别非常小。

It 's also possible to extend lxml itself if you write Python modules that are callable from XSLT or create custom Python or C extensions .

如果要编写能够从XSLT调用的Python模块，或创建定制的Python或C扩展，还可以扩展lxml。

If your task requires any serialization at all , lxml is a clear choice , but there are some tricks to get the best performance out of the library .

如果要执行要求序列化的任务，lxml无疑是最佳选择，但是需要使用一些技巧来获得最佳性能。

If , instead , your application relies mostly on internal , C-driven lxml features , it might be to your advantage to run it as a threaded application in a multiprocessor environment .

相反，如果应用程序主要依赖内部的、C驱动的lxml特性，那么可能适合将它作为多处理环境下的线程化应用程序运行。