local variable referenced before assignment python

Today, when Django is developed, the access page always has an error message. Local variable ' has ' referenced before assignment"Look at the data, it seems to say that you can't access the variable, check the code my view is writ

Def fun1 (): x = 5 def fun2 (): x *= 2 return x return fun2 () As above code, call FUN1 ()Run Error: unboundlocalerror:local variable ' x ' referenced before assignment. This is because for the FUN1 function, x is a local

First, meaning：The local variable XXX reference was not defined before.ii. Causes of ErrorsIs that Python does not have a variable declaration, so it finds the scope of the variable by a simple rule: if there is a variable

Yesterday I want to do a Python function in the number of send statistics, need to use global variables, as follows1COUNT =02 3 defsendonelinemsg (producer, listfromline):4Acsnstr =Listfromline[0]5Macstr = listfromline[1]6Onlinetimestr = listfromline[2]7msg = {'Clientmac': Macstr,'ACSN': Acsnstr,'Onlinetime': Onlinetimestr}8MSGSTR =json.dumps (msg)9 producer.produce (MSGSTR)TenCOUNT + = 1The error is reported, and the workaround is to add a row to the

Summarize: Internal functions, you can access the global variable internal functions, modify global variables, and the same name, Python will think that it is a local variable called the variable name (such as print sum) before th

The problem is very awkward, the outside definition of a variable xxx, and then in a Python function to reference this variable, and change its value, the results of the error local variable ' xxx ' referenced

When we write Python, we sometimes run into situations where we've already defined the variable n outside the function, printed it out inside the function, and then made the variable go up, and then ran into this error: unboundlocalerror:local variable ' xxx ' referenced

The number of leaf nodes and the number of layers of the book are obtained today while learning the third chapter of the book "Robot Learning Combat". An error occurred following the code code on the book: Source: def getnumleafs (mytree):Numleafs = 0Firststr = Mytree.keys () [0]Seconddict = Mytree[firststr]For key in Seconddict.keys ():If Type (Seconddict[key]). __name__ = = "Dict":Numleafs + + GETNUMLEAFS (Seconddict[key])ElseNumleafs + 1Return Numleafs Run Error: Traceback (most recent call

This code is to change the value of the global variable y,z, it seems that there is no problem, Y,z declared outside the function, the actual operation will be reported unbondlocalerror wrong. This is because of the Python variable name resolution principle: the LEGB principle. When you use a variable name that is not

Python basics-annotation-variable assignment, python assignment I. Notes # Note \ N line Separator \ Continue the previous row ''' *** ''' Multiline comment Ii. Basic Rules : Separate code block (Group) header $ tail Indent BLOCK statement code blocks are distingui

python variablesis a knowledge point that can't be bypassed in programming, Python variables, the code works correctly, and the value is especially important. variablesstored in-memory value, which means that when a variable is created, it is in memory open up a spaceBased on variablesData type, the interpreter allocates the specified memory and determines what d

, with large amounts of data, it is cumbersome to execute code so that it is time to store two of data in a variable, such as:studentnumber = "CoXie01"If you look at this variable name, a lot of people are looking at the face of the crazy, what is this big string of things? In the strict code, generally encountered this situation, the following two kinds of naming methods are used:underline naming method :T

, you bastard, write a bunch of things we all know. Come on, I want a refund. Then I'm here to say that the refund is not back AH.How to write a good variable?Let me cite one more example:x = "CoXieQqun"y = "725479218"z = x + y print(z)The result of the operation is:CoXieQqun725479218I don't know if you can read it, look at the variable and the value of the variabl