What happens when the following code segment executes if test.txt does not exist?
infile = open("test.txt", "r")

Question

BlackTom AI · Accepted Answer

Consider what happens when Python tries to open a file in read mode ("r") and the file does not exist. 
Option 1: 'All attempts to read from the file return random values.' This is inaccurate because there is no file to read from, and Python does not generate random values simply by attempting to read; the opened handle would fail before any read could occur. 
Option 2: 'The program raises an exception.' This is correct. In read mode, if the file is missing, Python raises a FileNotFoundError (an exception), signaling that the path cannot be opened for reading. 
Option 3: 'All attempts to read from the file return an empty string.' This would imply the file is opened successfully but empty; however, the open call itself would fail when the file is missing, so no read could return an empty string. 
Option 4: 'The file test.txt is created as a new empty file.' Opening in read mode does not create files; creation typically happens in write or append modes, so this option is incorrect in this context. 
In summary, the only behavior that aligns with attempting to open a non-existent file in read mode is that an exception is raised, preventing any read operation from proceeding.

Fal25_CS003C_74229 Ch. 7 Pre-Quiz (Remotely Proctored)

What happens when the following code segment executes if test.txt does not exist? infile = open("test.txt", "r")

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