strange partial function aciton

[luofeiyu]

code1 ok

from Tkinter import *
from functools import partial
fields = 'Name', 'Job', 'Pay'
    
def fetch(entries,event):
    for entry in entries:
       print 'Input => "%s"' % entry.get()        
    print  event
    
    
def makeform(root, fields):
    entries = []
    for field in fields:
        row = Frame(root)                          
        lab = Label(row, width=5, text=field)      
        ent = Entry(row)
        row.pack(side=TOP, fill=X)                  
        lab.pack(side=LEFT)
        ent.pack(side=RIGHT, expand=YES, fill=X)    
        entries.append(ent)
    return entries
          
    
if __name__ == '__main__':
          
    root = Tk()
    ents = makeform(root, fields)
    root.bind('<Return>', partial(fetch,ents))
    root.mainloop()

code2 fail i don't understand why ?

from Tkinter import *
from functools import partial
fields = 'Name', 'Job', 'Pay'
    
def fetch(entries,event):
    for entry in entries:
       print 'Input => "%s"' % entry.get()        
    print  event
    
    
def makeform(root, fields):
    entries = []
    for field in fields:
        row = Frame(root)                          
        lab = Label(row, width=5, text=field)      
        ent = Entry(row)
        row.pack(side=TOP, fill=X)                  
        lab.pack(side=LEFT)
        ent.pack(side=RIGHT, expand=YES, fill=X)    
        entries.append(ent)
    return entries
          
    
if __name__ == '__main__':
          
    root = Tk()
    ents = makeform(root, fields)
    root.bind('<Return>', partial(fetch,entries=ents))
    root.mainloop()

code3: fail i know the reason

from Tkinter import *
from functools import partial
fields = 'Name', 'Job', 'Pay'
    
def fetch(event,entries):
    for entry in entries:
       print 'Input => "%s"' % entry.get()        
    print  event
    
    
def makeform(root, fields):
    entries = []
    for field in fields:
        row = Frame(root)                          
        lab = Label(row, width=5, text=field)      
        ent = Entry(row)
        row.pack(side=TOP, fill=X)                  
        lab.pack(side=LEFT)
        ent.pack(side=RIGHT, expand=YES, fill=X)    
        entries.append(ent)
    return entries
          
    
if __name__ == '__main__':
          
    root = Tk()
    ents = makeform(root, fields)
    root.bind('<Return>', partial(fetch,ents))
    root.mainloop()

code4: ok

from Tkinter import *
from functools import partial
fields = 'Name', 'Job', 'Pay'
    
def fetch(event,entries):
    for entry in entries:
       print 'Input => "%s"' % entry.get()        
    print  event
    
    
def makeform(root, fields):
    entries = []
    for field in fields:
        row = Frame(root)                          
        lab = Label(row, width=5, text=field)      
        ent = Entry(row)
        row.pack(side=TOP, fill=X)                  
        lab.pack(side=LEFT)
        ent.pack(side=RIGHT, expand=YES, fill=X)    
        entries.append(ent)
    return entries
          
    
if __name__ == '__main__':
          
    root = Tk()
    ents = makeform(root, fields)
    root.bind('<Return>', partial(fetch,entries=ents))
    root.mainloop()

there are four codes,code1,cod e4 it's ok,i know why;
code2,code3,it' s not ok,i understand why code2 can't work,
would you mind to tell me why code3 can't work??
the output is:
Exception in Tkinter callback
Traceback (most recent call last):
File "/usr/lib/python2.7/lib-tk/Tkinter.py", line 1413, in __call__
return self.func(*args )
TypeError: fetch() got multiple values for keyword argument 'entries'

i don't understand it.