msg = "hello 123 WORLD"
#统计长度和小写字母个数
length =len(msg)
lower_count = sum(1 for ch in msg if ch.islower())
print("长度:",length)
print("小写字母个数:", lower_count)
#替换并转小写
new_msg = msg.replace("WORLD", "Python")
result = new_msg.lower()
print("结果:",result)
bXNnID0gImhlbGxvIDEyMyBXT1JMRCIKI+e7n+iuoemVv+W6puWSjOWwj+WGmeWtl+avjeS4quaVsApsZW5ndGggPWxlbihtc2cpCmxvd2VyX2NvdW50ID0gc3VtKDEgZm9yIGNoIGluIG1zZyBpZiBjaC5pc2xvd2VyKCkpCnByaW50KCLplb/luqbvvJoiLGxlbmd0aCkKcHJpbnQoIuWwj+WGmeWtl+avjeS4quaVsO+8miIsIGxvd2VyX2NvdW50KQoj5pu/5o2i5bm26L2s5bCP5YaZCm5ld19tc2cgPSBtc2cucmVwbGFjZSgiV09STEQiLCAiUHl0aG9uIikKcmVzdWx0ID0gbmV3X21zZy5sb3dlcigpCnByaW50KCLnu5PmnpzvvJoiLHJlc3VsdCk=