Python Basics 06 Coding and small Knowledge points supplement

The main contents of this section :

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2. encoding problem

? difference between. is and = =
1. ID ()
by ID () we can see the value of the variable table? The address in memory

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? encoded supplement
1. Python2 silent Yes yards so python2 more coded need to be in the beginning of the piece write :
#-*-Encoding:utf-8-*-

2. Python3 : The Unicode code is in the memory.

Encode backGu:
1.ASCII:EarliestThe encoding.??YesBritish?? writeWord?,?WriteWord?,Digital,?SomeSpecial characters.Not in?,
8A01Code, 8Abit, 1AByte
2.GBK:In?GbCode,?? containsTheAsciiCoding and medium-constant encoding. 16ABit, 2AByte
3.UNICODE:MillionCountryCode,?? containsTheWorldAllCountriesThe encoding of the word. 32ABit, 4AByteContainsThe
Ascii
4.UTF-8:Variable? degreeThe MillionCountryCode.IsUnicodeKind of reality . the most, the character occupies 8 bits.
1. English : 8bit 1byte
2. European Word : 16bit 2byte
3. in? : 24bit 3byte
in addition to ASCII code , other information cannot be converted directly .

InPython3In-memory.InRideOrder shipment?Stage.What makes the?UnicodeCoding.BecauseUnicodeis millionCountryCode.What inside
Can we go in?Explicitly?.So in the dataMass transferWhen you lose and store.ByInUnicode? More wasted SpaceAndResources.Need to put
UnicodeDump intoUTF-8OrGBKinto storage.HowWhat about the conversion?.InPython encode After the content can be entered? lost code . Its also original Data is just coded After performance form hair?

RememberLive: coding results and source string? To The results are based on different coding coded result
also differs we can see utf-8 encoding Yes 3 bytes gbk The encoding is 2 bytes .

Python Basics 06 Coding and small Knowledge points supplement