python调用from gmssl import sm2后，对sm2进行密钥生成代码的补充

import binascii
from random import choice
from . import sm3, func
from Cryptodome.Util.asn1 import DerSequence, DerInteger
from binascii import unhexlify
import random
# 选择素域，设置椭圆曲线参数

default_ecc_table = {
    'n': 'FFFFFFFEFFFFFFFFFFFFFFFFFFFFFFFF7203DF6B21C6052B53BBF40939D54123',
    'p': 'FFFFFFFEFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF00000000FFFFFFFFFFFFFFFF',
    'g': '32c4ae2c1f1981195f9904466a39c9948fe30bbff2660be1715a4589334c74c7'
         'bc3736a2f4f6779c59bdcee36b692153d0a9877cc62a474002df32e52139f0a0',
    'a': 'FFFFFFFEFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF00000000FFFFFFFFFFFFFFFC',
    'b': '28E9FA9E9D9F5E344D5A9E4BCF6509A7F39789F515AB8F92DDBCBD414D940E93',
}


class CryptSM2(object):

    def __init__(self, private_key, public_key, ecc_table=default_ecc_table, mode=0, asn1=False):
        """
        mode: 0-C1C2C3, 1-C1C3C2 (default is 1)
        """
        self.private_key = private_key
        self.public_key = public_key.lstrip("04") if public_key.startswith("04") else public_key
        self.para_len = len(ecc_table['n'])
        self.ecc_a3 = (
            int(ecc_table['a'], base=16) + 3) % int(ecc_table['p'], base=16)
        self.ecc_table = ecc_table
        assert mode in (0, 1), 'mode must be one of (0, 1)'
        self.mode = mode
        self.asn1 = asn1

    def _kg(self, k, Point):  # kP运算
        Point = '%s%s' % (Point, '1')
        mask_str = '8'
        for i in range(self.para_len - 1):
            mask_str += '0'
        mask = int(mask_str, 16)
        Temp = Point
        flag = False
        for n in range(self.para_len * 4):
            if (flag):
                Temp = self._double_point(Temp)
            if (k & mask) != 0:
                if (flag):
                    Temp = self._add_point(Temp, Point)
                else:
                    flag = True
                    Temp = Point
            k = k << 1
        return self._convert_jacb_to_nor(Temp)

    def _double_point(self, Point):  # 倍点
        l = len(Point)
        len_2 = 2 * self.para_len
        if l < self.para_len * 2:
            return None
        else:
            x1 = int(Point[0:self.para_len], 16)
            y1 = int(Point[self.para_len:len_2], 16)
            if l == len_2:
                z1 = 1
            else:
                z1 = int(Point[len_2:], 16)

            T6 = (z1 * z1) % int(self.ecc_table['p'], base=16)
            T2 = (y1 * y1) % int(self.ecc_table['p'], base=16)
            T3 = (x1 + T6) % int(self.ecc_table['p'