#!/usr/bin/env  python
#encoding:UTF-8
def showmenu():
        tmp="""
        (1)取五个数的和
        (2)取5个数的平均值
        (X)退出
        enter you choice:"""

def adder():
        alist=[]
        for i  in range(5):
                alist.append(int(raw_input('plesae input:')))
        return  sum(alist)
def diver():
        alist=[]
        for i in range(5):
                alist.append(int(raw_input('please input:')))
        sum1=float(sum(alist))
        avg=sum1/len(alist)
        return  avg
cmd={'1':adder(),'2':diver}
while True:
        while True:
                try:
                        choice=raw_input(tmp).strip()[0].lower()
                except  (EOFError):
                        choice='x'
                if  not choice  in '12x':
                        print  'invalid  option'
                else:
                        break
        if choice=='x':
                break
        cmd[choice]()
if  __name__=='__main__':
        showmenu()

Traceback (most recent call last):
  File "2-11.py", line 26, in <module>
    choice=raw_input(tmp).strip()[0].lower()
NameError: name 'tmp' is not defined