Liste au personnage

# 列表 转 字符串 (只有 字符串) ： 
li = [ " ety " , " xyz " , " hello " , " world " ] 
s = "" .join (li)
 print (s) 


s = " , " .join (a)
 impression (s) 

'' ' 
etyxyzhelloworld ety 
, xyz, bonjour, monde 
' ''