1. Example - error

name = "Forever Strong"
print(name.upper())
print(name.lower)

FOREVER STRONG
<built-in method lower of str object at 0x0000000002310670>
 
 
------------------
(program exited with code: 0)
 
请按任意键继续. . .

2. Example - correction

name = "Forever Strong"
print(name.upper())
print(name.lower())

References

[1] Yongqiang Cheng, https://yongqiang.blog.csdn.net/