Python2并不支持非ASCII码标识符. PEP的全称是Python Enhancement Proposal, 即Python增强提案. 这个3131提案创建于2007年5月. Python3于2008年12月发布.
Python code is written by many people in the world who are not familiar with the English language, or even well-acquainted with the Latin writing system. Such developers often desire to define classes and functions with names in their native languages, rather than having to come up with an (often incorrect) English translation of the concept they want to name. By using identifiers in their native language, code clarity and maintainability of the code among speakers of that language improves.
People claim that they will not be able to use a library if to do so they have to use characters they cannot type on their keyboards. However, it is the choice of the designer of the library to decide on various constraints for using the library: people may not be able to use the library because they cannot get physical access to the source code (because it is not published), or because licensing prohibits usage, or because the documentation is in a language they cannot understand. A developer wishing to make a library widely available needs to make a number of explicit choices (such as publication, licensing, language of documentation, and language of identifiers). It should always be the choice of the author to make these decisions - not the choice of the language designers.
有人表示库如果是其他语言命名, 不懂这一语言的使用者就不会输入API名了. 回应是库开发者有权根据需要进行设计, 这与其他制约因素(版权,文档是外文等等)类似. 开发者如果想要库被最广泛地使用, 自然会考虑到所有这些因素. 而这, 应该是开发者的决定, 而不是语言设计者的.