def size(self):
res_p = KeyVal_C_API.new_long_ptr()
errcode = KeyVal_C_API.KeyVal_size(res_p, self.kv)
if errcode:
raise Exception("[ERROR] KeyVal.size")
res = KeyVal_C_API.long_ptr_value(res_p)
KeyVal_C_API.delete_long_ptr(res_p)
return res
