代码报错，求大神指点

Question

file_name = input('请输入需要打开的文件名：')
f = open(file_name)
print('文件的内容是：')
for each_line in f:
    print(each_line)

运行之后出现报错如下：

请输入需要打开的文件名：1.txt
文件的内容是：
Traceback (most recent call last):
  File "C:/Users/涤非/Desktop/test2.py", line 4, in <module>
    for each_line in f:
UnicodeDecodeError: 'gbk' codec can't decode byte 0xff in position 0: illegal multibyte sequence

Answer 1

f = open(filename, encoding="gbk")

Answer 2

编码的问题