PCEP Timed Practice Test 3 — 10 Questions

Question 1

Match each Python data type to its description.

Question 2

Match each exception type to its description.

Question 3

Match each Python function to its description.

Question 4

Match each Python concept to its description.

Question 5

Refer to the exhibit. What is the output?

Accepted Answer

20
20. The inner function uses nonlocal to modify the variable x from the enclosing scope. After calling inner(), x becomes 20 and is printed. Then outer prints x which is also 20. So output is 20 and 20.

Answer

10
20

Answer

10
10

Answer

20
10

Question 6

A developer wants to read a floating-point number from user input and compute its square. Which code snippet correctly accomplishes this?

Accepted Answer

num = float(input()); result = num ** 2. Option B is correct because it uses `float(input())` to convert the user's input (which is always a string) into a floating-point number, and then computes the square using the exponentiation operator `**`. This ensures that decimal values are handled correctly, which is required for computing the square of a floating-point number.

Answer

num = input(); result = num * num

Answer

result = input() ** 2

Answer

num = int(input()); result = num ** 2

Question 7

Which TWO of the following are valid Python variable names? (Choose two.)

Accepted Answer

var123. Option B (var123) is correct because Python variable names must start with a letter or underscore, and can contain letters, digits, or underscores. 'var123' starts with a letter and contains only valid characters, making it a legal identifier.

Answer

for

Answer

my-var

Answer

1var

Question 8

A Python script contains the following line: x = 5. Later in the script, the programmer wants to check if x is an integer. Which of the following is the BEST way to perform this check?

Accepted Answer

if isinstance(x, int):. Option A is correct because `isinstance(x, int)` is the recommended way to check if a variable is an instance of a specific class in Python. It handles inheritance correctly (e.g., if `x` were a subclass of `int`) and is more robust than directly comparing types with `type()`. This aligns with Python's duck typing philosophy and is the standard approach in professional code.

Answer

if x is integer:

Answer

if x == 'integer':

Answer

if type(x) == int:

Question 9

A Python program is designed to process user input and store results in a dictionary. The code uses the statement: my_dict[user_key] = value. Under which condition will this statement raise a TypeError?

Accepted Answer

If the key is a list.. Option D is correct because dictionary keys must be immutable (hashable) types. A list is mutable and therefore unhashable, so using it as a key in a dictionary assignment raises a TypeError. The statement `my_dict[user_key] = value` will fail at runtime if `user_key` is a list.

Answer

If the key is None.

Answer

If the key already exists and you try to assign a different value.

Answer

If the key does not already exist in the dictionary.

Question 10

A developer writes a loop to sum numbers from 1 to 10. The code outputs 55, but the expected sum is 55. However, the loop uses a range that includes 0. Which range should be used to achieve the correct sum?

Accepted Answer

range(1,11). Option B (range(1,11)) is correct because range(start, stop) generates numbers from start inclusive to stop exclusive. To sum numbers 1 through 10, the range must start at 1 and end at 11 (so 10 is included). The loop that used range(0,11) included 0, but since adding 0 does not change the sum, the output was still 55 — however, the question asks for the range that achieves the correct sum without including unnecessary values.

Answer

range(0,11)

Answer

range(0,101)

Answer

range(1,10)