Python variables cannot start with numbers.

The following small series will bring you a python variable that cannot be explained in detail with numbers. I think it is quite good. I will share it with you now. I would also like to give you a reference. Let's take a look at it. when writing a python function, we accidentally found a problem: the variable in python cannot start with a number. the following function defines a variable 3_num_varchar, and an error is reported during execution.

The function is as follows:

def database_feild_varchar_trans(in_feild):  '''  transfer the feild if varchar then 3times lang else no transfer  '''  feild_split = in_feild.split(' ')  is_varchar = feild_split[1].find('VARCHAR')  if is_varchar >= 0 :    num_varchar = feild_split[1].replace('VARCHAR','').replace('(','').replace(')','')     print (num_varchar)    3_num_varchar = num_varchar*3    feild_split[1] = feild_split[1].replace(str(num_varchar),str(3_num_varchar))    return feild_split  else:    print ('The feild type is not varchar')    return feild_split

The error message is as follows:

>>> Runfile ('E:/procedure/python/projects/others/table_test.py ', wdir = 'E:/procedure/python/projects/others ') traceback (most recent call last): File"
 
  
", Line 1, in
  
   
File "D: \ Python33 \ lib \ site-packages \ spyderlib \ widgets \ externalshell \ sitecustomize. py ", line 699, in runfile execfile (filename, namespace) File" D: \ Python33 \ lib \ site-packages \ spyderlib \ widgets \ externalshell \ sitecustomize. py ", line 88, in execfile exec (compile (open (filename, 'RB '). read (), filename, 'exec '), namespace) File "E:/procedure/python/projects/others/table_test.py", line 20 3_num_varchar = int (num_varchar) * 3 ^ SyntaxError: invalid syntax: replace the variable 3_num_varchar with num_varchar_3. The program runs successfully as follows: import osimport sysstr1 = 'AAA varchar (10) 'def evaluate (in_feild ): '''transfer the feild if varchar then 3 times lang else no transfer ''' 'feild_split = in_feild.split ('') is_varchar = feild_split [1]. find ('varchar ') if is_varchar> = 0: num_varchar = feild_split [1]. replace ('varchar ',''). replace ('(',''). replace (')', '') print (num_varchar) num_varchar_3 = num_varchar * 3 feild_split [1] = feild_split [1]. replace (str (num_varchar), str (num_varchar_3) return feild_split else: print ('The feild type is not varchar ') return feild_splitprint (database_feild_varchar_trans (str1 ))
  
 

Running result:

>>> runfile('E:/procedure/python/projects/others/table_test.py', wdir='E:/procedure/python/projects/others')The feild type is not varchar['aaa', 'varchar(10)']

The above python variable cannot be explained in the beginning with a number, that is, all the content that I have shared with you. I hope you can give me a reference and support me a lot.