import re
p = re.compile('^(?=[^a-z]*([a-z]))(?=[^A-Z]*([A-Z]))(?=[^0-9]*([0-9]))', re.MULTILINE)
test_str = "adkkeEdkj$4\n4jdkg5UU"
print(re.findall(p, test_str))
aW1wb3J0IHJlCnAgPSByZS5jb21waWxlKCdeKD89W15hLXpdKihbYS16XSkpKD89W15BLVpdKihbQS1aXSkpKD89W14wLTldKihbMC05XSkpJywgcmUuTVVMVElMSU5FKQp0ZXN0X3N0ciA9ICJhZGtrZUVka2okNFxuNGpka2c1VVUiCnByaW50KHJlLmZpbmRhbGwocCwgdGVzdF9zdHIpKQ==