Assume there are only two files in a folder. One is a text file called my$\_$file.txt and the other is a Python file that contains the following program. What kind of exception will the following Python program raise?

filename $=\text{'}$my$\_$file.txt$\text{'}$

file $=$ open$(\text{'}$my$\_$file.txt$\text{'})$

contents $=$ file.read$()$