python檢測手機號碼是否合法

!/usr/bin/python
#encoding:utf-8
#這是一個用來檢測用戶輸入手機號碼是否合法的小腳本。

def phonecheck(s):
        #號碼前綴，如果運營商啟用新的號段，只需要在此列表將新的號段加上即可。
        phoneprefix=['130','131','132','133','134','135','136','137','138','139','150','151','152','153','156','158','159','170','183','182','185','186','188','189']
        #檢測號碼是否長度是否合法。
        if len(s)<>11:
                print "The length of phonenum is 11."
        else:
                #檢測輸入的號碼是否全部是數字。
                if  s.isdigit():
                        #檢測前綴是否是正確。
                        if s[:3] in phoneprefix:
                                print "The phone num is valid."
                        else:
                                print "The phone num is invalid."
                else:
                        print "The phone num is made up of digits."


if __name__=="__main__":
        phonenum=raw_input("Input your phone num:")
        phonecheck(phonenum)