Python = = and is, encoding and decoding

is and = == = Compare values on both sides

' Alex '  'Alex'print(a = = b  )=ten = tenprint (n= = [= = [Li1]print(= = = Li2) True

is compare memory address query memory address ID ()

' Alex ' Print (ID (a))   # 36942544  memory address  = tenprint(ID (n))     # 1408197120  = [All in all]print(li)      #38922760

A ='[email protected]'A1='[email protected]'Print(A isA1)#FalesN= 5//2N1= 2Print(n isN1)#Truea='a'*21b='a'*21Print(A isb

Small Data Pool range: -5~256

n =-6=-6print is N1)  #False= 5= 5Print   is N1)    #True= 257= 257printis N1)     #True

String

The memory address within a single string of * 20 is the same (the string cannot have special symbols such as: +-*/@!). And so on

A single string *20 above the memory address is not the same

' [email protected] '  '[email protected]'print is A1)    #  fale 

' aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa '  'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa'print is # True

List

Li =[1,2,3=[1,2,3]print is Li2)  #False

Meta-group

Tu = (tu1= (all in a)print is)   #  False

Dictionary

Dic1 = {'name':'Alex'= {'name ' ':'Alex'}print is dic)    #  False

Note: Pycharm is a pit, and all the same strings in a py file are generally using the same memory address

Encoding and decoding

The codes are: asiic,unicode,gbk,utf-8,utf-16

ASCII code: Chinese is not supported, English, numerals, symbols, 8 bits, one byte

GBK Code: GB Code, support Chinese, English, numerals, symbols. English every 16 bits two bytes, Chinese 16 bit two bytes

Unicode: Universal code, support Chinese, English, numerals, symbols, English 32-bit four bytes. Chinese 32 bit four bytes

Utf-8: Currently the most used encoding is the variable length of the universal code, with a minimum of 8 bits. English 8 bit one byte Chinese 24 bit three bytes

Unicode is used in the program run phase in Python3 to display all content

Bytes Type: Transport and storage are all using bytes

The default is to use Utf-8 when Pycharm storage

. Encode (' code ') after getting the plaintext after encoding the corresponding binary bytes

. Decode (' code ') decodes the encoded bytes into the corresponding plaintext

Both operations are linked through Unicode as an intermediate bridge.

s ='Alex'#Print (S.encode (' Utf-8 ')) # encoded encode (' Utf-8 ') Utf-8 is the type of encoding to be encoded into#Print (S1.decode (' Utf-8 ')) ##bytes#b ' Alex '#s = ' hungry '#S1 = s.encode (' GBK ') #b ' hungry ' #b ' \xe9\xa5\xbf\xe4\xba\x86\xe5\x90\x97 '#Print (S.encode (' GBK ')) #b ' \xb6\xf6\xc1\xcb\xc2\xf0 '#print (S1)#Print (S1.decode (' Utf-8 '))

Note: What to encode what to decode or you will be confused!

Python = = and is, encoding and decoding