执行python脚本时提示“TypeError: can only concatenate str (not "bytes") to str”错误，如图示所示：

原脚本  

        vk = self.sk.get_verifying_key()
        vk_hex = binascii.hexlify(vk.to_string())

        vk_x_separated = ""
        vk_x_str = vk_hex[0:64]
        for i in range(0, len(vk_x_str), 2):
            vk_x_separated = "0x" + vk_x_str[i:i+2] + ", " + vk_x_separated
原因是vk_x_str[i:i+2]是byte类型，链接需要str类型，需将vk_x_str[i:i+2]转换为str类型。

更改后的脚本

        vk = self.sk.get_verifying_key()
        vk_hex = binascii.hexlify(vk.to_string())

        vk_x_separated = ""
        vk_x_str = vk_hex[0:64]
        for i in range(0, len(vk_x_str), 2):
            vk_x_separated = "0x" + str(vk_x_str[i:i+2]) + ", " + vk_x_separated
运行新脚本不再提示错误