coursera full stack web development review

18. License plate zoning, the following license plate is given. According to the information of the license plate, the number of license plate holdings in each province is analyzed. (Upgrade question)result = {} for in cars: = locals[car[0]] = result.get (location, 0) +1print(Result)result = {} forCarinchCars#Car Brandfirst_name = car[0]#ShandongLocation =Locals[first_name]#to statistics ifResult.get (location) = = None:#If you get the current location. The number of corresponding vehic

9. Dictionary dic,dic = {' K1 ': "v1", "K2": "V2", "K3": [11,22,33]}A. Please loop out all the keysFor I in Dic.keys ():Print (i)B. Please loop out all the value for inch dic.values (): Print (i)C. Please loop out all the keys and value for inch Dic.items (): Print (I,J)D. Add a key-value pair in the dictionary, "K4": "V4", and output the added dictionaryDic.setdefault ('K4','v4')print(DIC)E. In the modified dictionary, the value of "K1" corresponds to "Alex", Output the modified diction

16. Movie Scoring: The program gives a list of several movies that are currently being released. Voted by the user for each movie.Finally, the user's voting information is published in LST = [' Beijing meets Seattle ', ' Save Mr. Wu ', ' American past ', ' the beautiful legend of Sicily ']Result: {' Beijing meets Seattle ': 99, ' Save Mr. Wu ': 80, ' The American Past ': 6, ' The Beautiful Tales of Sicily ': 23}LST = ['Beijing meets Seattle','Save Mr. Wu','The American past','the beautiful legen

11. The element classification has the following value li= [11,22,33,44,55,66,77,88,99,90], all values greater than 66 are saved to the first key of the dictionary, the value less than 66 is saved to the value of the second key.That is: {' K1 ': List of all values greater than 66, ' K2 ': List of all values less than 66}dic={'K1':[],'K2': []} li= [11,22,33,44,55,66,77,88,99,90] forIinchLi:ifI > 66: dic['K1'].append (i)Else: dic['K2'].append (i)Print(DIC)Python3.6

manipulation objectsCheck: object. Name # print (aq.name)Increment: Object. job= "Student" # aq.job= "Stu"Delete: Del object. AgeChange: Object. gent= "Male"6. The static variables in the object operation class can only be queried, cannot be deleted or modified.The object name. Variable (level) in class # print (Aq.level)7. Methods in the Object execution classThe object name. Walk () # Aq.walk () # automatically receives object space without having to pass arguments to the self position.Add: _

#class Eat:#def __init__ (self):#print (' Eat ')#def Eat (self):#print (' Eat ')##class Run:#def __init__ (self):#print (' Run ')#class Cat (eat,run):#def __init__ (self):#print (' This is a cat ')#def Eat (self):#print (' This is sons eat ')#class Dog (eat,run):#def __init__ (self):#print (' This is a dog ')#P1=cat ()#p1.eat ()#class Father:#def __init__ (self,name,age,gender):#Self.name=name#Self.age=age#Self.gender=gender#def test (self):#print (' This is Father S ')#class Son (Father):#def _

typically start with uppercase def __init__ (self,age): self.age =age# gives self an age method with a value of input age,,p.age=age name=" yehaibin " # data properties # for def Qiong (self): print ( ' zhengzaitutan " ,self.age ) del china.name 2.1.4 Increase　　　　classChina:#when declaring a class, it is usually preceded by uppercase def __init__(self,age): Self.age=age#Given to self an age method, the value of the input age,,p.age=ageName='Yehaibin'#Data Properties #

,PRICE,ADDR): Self.name=name Self.priod=priod Self.price=Price self.addr=AddrclassTeacher:def __init__(self,school): Self.school=School##############School1=school ('Sdau','Beijing',{'Linux':'Class 1','python':'Class 2'})#The school is already there, let the students chooseSchool2=school ('Yingshangyizhong','Shanghai',{'Go':'Class 3'})#Create a courseLesson1=lesson ('python','50week', 150,'Beijing')#courses are available, so students can chooseLesson2=lesson ('Linux','30week', 60,'Beijing') Less

cursor movement are in bytes such as Seek,tell,truncateAttention:1. Seek has three modes of movement 0,1,2, of which 1 and 2 must be performed in B mode, but regardless of which mode is moved in bytes unitsSeek controls the movement of the cursor as a reference to the beginning of the file.Tell the position of the current cursor2. Truncate is truncated file, truncation must be write mode, but can not be opened with W or w+, because that will directly empty the file, so truncate to r+ or a or a

from the real work2: Code easier to organize, clearer, complex tasks easier to implement;3: No doubt, more secure, not due to some small negligence to make the program accidentally collapsed;Iii. when to use exception handlingTry...except should be used sparingly, because it is an exception-handling logic that you attach to your program, which is not related to your main work.This kind of things add more, will lead to your code readability is poor, only in some abnormal unpredictable circumstan

') ) Tcp_socket_client.close ()if __name__=='__main__': Ip_port=('127.0.0.1', 9999) BufSize=1024Client_handler (ip_port,bufsize) client (illegal: do not know Secret_key)Client (illegal: do not know Secret_key)Socketserver ModuleImplementation of a one-to-many interaction mode between server and client based on TCP protocolImportSocketserverclassMyServer (socketserver. Baserequesthandler):defHandle (self):#Self.request is the equivalent of a conn whileTrue:Print(self.client_address) msg=

the task is waiting to be executedThe queue is a built-in lock, so it is safe for other applications to call it.When it comes to manual locking, it is unsafe. Commonly used is the message middlewareGalena with no return valueClose and join paired useImport timefrom multiprocessing Import pooldef Wahaha (i): time.sleep (1) print (' * ' * i) if __name__ = = ' __main__ ': p = Pool (5) # The recommended number is CPU cores +1 for I in range (5): P.apply_async (Func=wahaha

1. Formatted output uses string concatenation to form a template: This leads to formatted output: (Personal business Card making) use of formatted output: The% placeholder S is the character, and D represents the number%s%d%r??? The first format: (Must be one-to-one) the second format: (no one by one correspondence) Note: Formatted output, in the formatted output, the simple representation of% need to use percent of 2.while......else ... (The specific scene will be used) when the while loop is n

#max, Min,zippeople1={ 'Age1': 123,'Age2': 56,'Age3': 554,'Age4': 67,'Age5': 234,'Age6': 34,'Age7': 45} #取出key值可以知道对应值 with zipPrint(List (max (Zip (people1.values (), People1.keys () )))Print(list (Zip (People1.values (), People1.keys ()))) Max,min parameter (the object that can be used, the key method (typically a lambda expression)) people=[ {'name':'Lu',' Age': 123}, {'name':'Jia',' Age': 134}, {'name':'Cheng',' Age': 143}, {'name':'Lu',' Age': 112}]Print(Max (people,key=Lambd

#读1 f=open ('d:\\k.py', encoding='UTF8') 2 print (F.readline ()) 3 print (F.readline ()) 4 print (F.readline ()) #读一行readline5print (f.readable ()) #读全部, converting each line to a list string 6print (F.readlines ())7 f.close ()#写文件F=open ( ' li Chen ','w') f.write ('1244\ n43564\ngergre\nghhrt\n') f.writelines (['fsdgfwsdg', ' 3242 ']) # A String f.close () than required#追加F=open (' li Chen ','a') #a mode append f.write ( ' FDHDH ' ) f.write ('hgfbf') f.close ()#总结加其它#打开文件模式R

#!/usr/bin/env Python can declare the Python interpreter used by Liunx (unique)Coding#-*-Coding:utf-8-*-Python2 have Chinese language to add the code in the header file Plus, Python3 do not use, the default is Utf-8 (also can be written UTF8)Python syntax#变量名1. Letters2. Digital3. Underline#永远等待 until the user enters a value, n generation refers to the value entered by the userN=input (' Please enter user name: ')#条件语句　If condition:Statement blockElif Conditions:Statement blockElseStatement bloc

not changed, to add the function of timingNested functions:def foo (): Print ('in thefoo') def Bar (): Print ('in thebar') bar () foo ()Combine the above three implementations of adorners:Import TimedefTimer (func):#timer (Text1) func=text1 adorner function defWrapper (*args,**Kwargs): Start_time=time.time () func ()#Run Text1Stop_time =time.time ()Print('The Fun run time is %s'% (stop_time-start_time)) returnWrapper@timer#Text1 = Timer (Text1) This step is to pass the Tex

receives the value after next.4. Concurrent runsRequirements Analysis: Two functions, one function calls another function, and then saves the state in such a way.defChibaozi (name):Print('I'm starting to eat buns.') while1: Baozi=yield Print('This is the bun I ate.%s'%Baozi)defZuo (): S1=chibaozi ('Yehaibin') s1.__next__() forIinchRange (10): S1.send ('Lvelvelve') Zuo ()When running Zuo, each cycle, Chibaozi will do one action, and then save the state, which is yield. #其实我现在还不太懂,

, iterate, using the next method continuously until an exception is obtained, and the iterator ends. 3. Why Use iteratorsThe benefit of iterators: The iterator makes the data into memory for each time it is next. If it is a list, a large amount of memory to go into memory, the data is more likely to cause the crashLike what:The sum of the list (range (1000000)) is calculated and the data needs to be put into memory at once.In the case of iterators, using one data at a time, the first 1+2, the se

ID (variable): Returns a memory addressK1 is K2: Determine if their memory address is consistentK1 = = K2: Determine if their values are consistentSmall Data pools:-5-256STR: the same stringSTR * INT: Their length is not more than 20, the memory is consistentTheir memory addresses are all the same.CodingUse UTF-8 or GBK encoding during transferIn memory: The encoding is Unicode during our program's RunIn a program, a string can be encoded into a bytes type of datacode encode ()Grammar:Variable