2023学年完整公开课版6Pythonannotation

Pythonannotation2learningtasksUsecommentsinPython3TheknowledgeobjectiveUnderstandwhatannotationsdoLearnhowtowritePythoncomments01AbilityaimProficientinPythonannotationscanwritecommentsinrealdevelopment02learningtarget4CodeannotationWhywritecodecommentsPythoncomments1.Itisconvenienttoviewthecodeyouhavewritten;2.ThereisalargeflowofInternettalents.Inordertobettermaintaintheproject,appropriatenotesneedtobewritten.InPython,commentsaredividedintosinglelinecomments,multilinecommentsandspecialcomments.5PythonannotationSingle-LineCommentsInPython,asinglelinecommentisidentifiedwith#.WhenyouuseXinyourcode,anydatatotherightofitisignored.Youcanusesinglelinecommentsmultipletimesinsuccessioninsteadofmultilinecomments,butthatisnotrecommended.6PythonannotationmultilinecommentInPython,multilinecommentsaregenerallyusedtocommentclassdocumentsandfunctiondocuments,startingwiththreequotesandendingwiththreequotes.Thesethreequotescanbesinglequotes'ordoublequotes'.7PythonannotationSpecialnotes#!/usr/bin/envpythonThisnotemeans:PythontellsLinuxwhichpathtofindPythontranslator.#-*-coding:utf-8-*-Thisannotationmeans:tellthePythoninterpreterhowtointerprettheencodingtypeinthestring.8PythonannotationNoterequirements#!/usr/bin/envpython1.Itmustbethefirstlineofthefile2.Youmustuse#!Atthebeginning#-*-coding:utf-8-*-1.Basicallyinthesecondlineofthefile,inthe#!Thenextlinefrom/usr/bin/envpython2.YoumustuseChinesewhenitappearsinyourdocuments9PythonannotationNoterequirements#!/usr/bin/envpython1.Itmustbethefirstlineofthefile2.Youmustuse#!Atthebeginning#-*-coding:utf-8-*-1.Basicallyinthesecondlineofthefile,inthe#!Thenextlinefrom/usr/bin/envpython2.YoumustuseChinesewhenitappearsinyourdocuments10PythonannotationNoterequirementsEveryPythonfileusuallybeginswithanoteaboutwhatthemodule,thePythonfile,does,afewcaveats,andanyerrorsthatmightoccur.Eachclassisfollowedbyadescriptionoftheclassanditsusage.Eachfunctionmustbefollowedbyamulti-linecomment,commentsoftencontaininstructions,note.Addone-linecommentswherenecessary.11Summaryofk