def get_first_letter(char): 
 
   char=char.encode('GBK') 
 
    
 
   if char<b"\xb0\xa1" or char>b"\xd7\xf9": 
 
       return "" 
 
   if char<b"\xb0\xc4": 
 
       return "a" 
 
   if char<b"\xb2\xc0": 
 
       return "b" 
 
   if char<b"\xb4\xed": 
 
       return "c" 
 
   if char<b"\xb6\xe9": 
 
       return "d" 
 
   if char<b"\xb7\xa1": 
 
       return "e" 
 
   if char<b"\xb8\xc0": 
 
       return "f" 
 
   if char<b"\xb9\xfd": 
 
       return "g" 
 
   if char<b"\xbb\xf6": 
 
       return "h" 
 
   if char<b"\xbf\xa5": 
 
       return "j" 
 
   if char<b"\xc0\xab": 
 
       return "k" 
 
   if char<b"\xc2\xe7": 
 
       return "l" 
 
   if char<b"\xc4\xc2": 
 
       return "m" 
 
   if char<b"\xc5\xb5": 
 
       return "n" 
 
   if char<b"\xc5\xbd": 
 
       return "o" 
 
   if char<b"\xc6\xd9": 
 
       return "p" 
 
   if char<b"\xc8\xba": 
 
       return "q" 
 
   if char<b"\xc8\xf5": 
 
       return "r" 
 
   if char<b"\xcb\xf9": 
 
       return "s" 
 
   if char<b"\xcd\xd9": 
 
       return "t" 
 
   if char<b"\xce\xf3": 
 
       return "w" 
 
   if char<b"\xd1\x88": 
 
       return "x" 
 
   if char<b"\xd4\xd0": 
 
       return "y" 
 
   if char<b"\xd7\xf9": 
 
       return "z"