18位統(tǒng)一代碼最后一位計算方法如下：
```
def unioncode_checknum(code):
? ? alpha_to_num_map={'A':10,'B':11,'C':12,'D':13,'E':14,'F':15,'G':16,'H':17,'J':18,'K':19,'L':20,'M':21,'N':22,'P':23,'Q':24,'R':25,'T':26,'U':27,'W':28,'X':29,'Y':30}
? ? num_to_alpha_map={}
? ? for k,v in alpha_to_num_map.items():
? ? ? ? num_to_alpha_map[v]=k
? ? print(num_to_alpha_map)
? ? weights = [1,3,9,27,19,26,16,17,20,29,25,13,8,24,10,30,28]
? ? total = 0
? ? for i in range(len(code)):
? ? ? ? c = code[i]
? ? ? ? if?not?c.isdigit():
? ? ? ? ? ? total+=alpha_to_num_map[c]*weights[i]
? ? ? ? else:
? ? ? ? ? ? total+=int(c)*weights[i]
? ? pos = 31-(total%31)
? ? if pos==31:
? ? ? ? return 0
? ? if pos<10:
? ? ? ? return pos
? ? else:
? ? ? ? return num_to_alpha_map[pos]
```
統(tǒng)一社會信用代碼定義：
