练习

请写一个能处理去掉 = 的base64解码函数：

# -- coding: utf-8 --



import base64



def safe_base64_decode(s):



pass



# 测试:

assert b'abcd' == safe_base64_decode(b'YWJjZA=='), safe_base64_decode('YWJjZA==')

assert b'abcd' == safe_base64_decode(b'YWJjZA'), safe_base64_decode('YWJjZA')

print('Pass')