Exam2021_01

Question 1

Answer 1

Question 2

Answer 2

Question 3

Answer 3

Question 4

Answer 4

my_arr is reshaped to have 3 columns, and the number of rows is inferred automatically by numpy (using -1).

The shape of my_arr would be (2, 3) because the original array has 6 elements, and reshaping it to have 3 columns results in 2 rows.

The reshaped array would look like this:

[[0 1 2]
[3 4 5]]

Question 5

Answer 5

Question 6

Answer 6

Question 7

Answer 7

Question 8

Answer 8

Question 9

Answer 9

Question 10

Answer 10

Question 11

Answer 11

Question 12

Answer 12

Question 13

Answer 13

Question 14

Answer 14

Question 15

Answer 15

Question 16

Answer 16

The line my_arr[0] would select the first 2D array (of shape (4, 5)) from the 3D numpy array my_arr.

Question 17

Answer 17

Question 18

Answer 18

Question 19

Answer 19

Question 20

Answer 20

Question 21

Answer 21

The line my_arr[0, 0] would select the first 1D array (of shape (3,)) from the 3D numpy array my_arr.

Question 22

Answer 22

Question 23

Answer 23

Question 24

Answer 24

The AttributeError is raised but not caught by the except block because the except block is only looking for a ValueError. The finally block executes regardless of whether an exception was raised or not, and after the finally block executes, the AttributeError will propagate up the call stack.

So, the output will be:

done

And then the AttributeError will be raised.

Question 25

Answer 25

Question 26

Answer 26

D is correct

The key point is that once an exception is caught in an except block, it stops propagating unless you explicitly re-raise it (using the raise statement). In this code, the except block just prints a message and doesn’t re-raise the error, so the exception is fully handled at that point.

If you wanted the ValueError to continue propagating, you would need to add a raise statement in the except block, like this:

try:
    a_function()
except ValueError:
    print("there was an exception!")
    raise  # This would make the error continue propagating
finally:
    print("done!")

Code Explanation:

1. The code enters the try block
2. a_function() is called and raises a ValueError
3. Because ValueError was raised, execution jumps to the matching except ValueError block
4. The except block prints “there was an exception!” and handles the error (essentially catching and stopping it from propagating further)
5. After either the try block completes successfully OR an exception is handled, the finally block always executes
6. The finally block prints “done!”
7. The code continues normal execution because the exception was handled