PCEP Functions, Tuples, Dictionaries and Exceptions Practice Test 6 — 15 Questions

Question 1

A developer wants to use a tuple to store the names of the months. They attempt to change an element: months = ("Jan","Feb","Mar"); months[1] = "Februar". What is the result?

Accepted Answer

A TypeError is raised. Tuples in Python are immutable, meaning their elements cannot be changed after creation. Attempting to assign a new value to an index of a tuple (e.g., months[1] = "Februar") raises a TypeError, not a ValueError or AttributeError. This is because the assignment operation is not supported for tuple objects.

Answer

The tuple is updated to ("Jan","Februar","Mar")

Answer

A ValueError is raised

Answer

An AttributeError is raised

Question 2

A developer writes a function that appends an item to a list: def add_item(item, my_list=[]): my_list.append(item); return my_list. They call add_item(1) twice. What are the return values of the two calls?

Accepted Answer

[1] and [1,1]. The default argument `my_list=[]` is evaluated only once at function definition time, not each time the function is called. Therefore, the first call `add_item(1)` appends 1 to the same list object, returning `[1]`. The second call appends another 1 to that same list, returning `[1, 1]`. This is a classic Python gotcha involving mutable default arguments.

Answer

[1] and [1]

Answer

TypeError

Answer

[1] and [2]

Question 3

In a try-except block, a developer has two except clauses: except ValueError: and except: (bare except). If the code in the try block raises a ValueError, which except clause is executed?

Accepted Answer

The ValueError except clause. When a ValueError is raised in the try block, Python searches the except clauses in the order they appear. It finds the first matching clause, which is `except ValueError:`, and executes it. The bare `except:` clause is only reached if no preceding named except clause matches the exception type.

Answer

Both in order

Answer

Neither; program crashes

Answer

The bare except clause

Question 4

Given a list of names = ['Alice', 'Bob', 'Charlie'], a developer wants to create a dictionary mapping each name to its length. Which expression accomplishes this?

Accepted Answer

{name: len(name) for name in names}. It uses a dictionary comprehension that iterates over each name in the list, using the name as the key and the result of `len(name)` as the value. This directly maps each name to its length, which is exactly what the developer wants.

Answer

{len(name): name for name in names}

Answer

{name: len for name in names}

Answer

{name: length for name in names}

Question 5

A function is defined as: def min_max(nums): return min(nums), max(nums). What type of value does it return?

Accepted Answer

A tuple. The function `min_max` uses `return min(nums), max(nums)`, which is a comma-separated list of expressions. In Python, when multiple values are returned separated by commas, they are automatically packed into a tuple. Therefore, the function returns a tuple containing the minimum and maximum values.

Answer

A set

Answer

A dictionary

Answer

A list

Question 6

A function is defined as: def func(*args, **kwargs): print(args, kwargs). It is called as func(1, 2, a=3, b=4). What is printed?

Accepted Answer

(1, 2) {'a': 3, 'b': 4}. The function uses `*args` to capture positional arguments into a tuple and `**kwargs` to capture keyword arguments into a dictionary. When called as `func(1, 2, a=3, b=4)`, `args` becomes `(1, 2)` and `kwargs` becomes `{'a': 3, 'b': 4}`, so `print(args, kwargs)` outputs `(1, 2) {'a': 3, 'b': 4}`. Option B is correct because it matches this exact output.

Answer

(1, 2, a=3, b=4)

Answer

TypeError

Answer

[1, 2] {'a': 3, 'b': 4}

Question 7

A dictionary student = {'name': 'John', 'age': 20}. To safely get the grade with a default of 'N/A', which code should be used?

Accepted Answer

student.get('grade', 'N/A'). The `get()` method of a dictionary safely retrieves the value for a given key, returning a default value (here `'N/A'`) if the key does not exist. This avoids raising a `KeyError` when the key `'grade'` is missing from the dictionary.

Answer

student['grade']

Answer

student.fetch('grade', 'N/A')

Answer

student['grade'] or 'N/A'

Question 8

A developer wants to raise a ValueError with a custom message when a negative number is passed. Which code is correct?

Accepted Answer

raise ValueError("Negative input not allowed"). In Python, raising an exception with a custom message requires passing the message as an argument to the exception constructor: `raise ValueError("Negative input not allowed")`. This creates a ValueError instance with the specified message, which is the standard and only syntactically valid way to include a custom message in a raise statement.

Answer

raise ValueError "Negative input not allowed"

Answer

raise ValueError() + "Negative input not allowed"

Answer

raise new ValueError("Negative input not allowed")

Question 9

Consider the code: try: try: raise TypeError except ValueError: print('A') except TypeError: print('B') finally: print('C'). What is printed?

Accepted Answer

B and C. The inner `try` raises a `TypeError`. The inner `except ValueError` does not catch it, so the exception propagates to the outer `except TypeError`, which catches it and prints 'B'. The `finally` block always executes, printing 'C'. Thus, the output is 'B' and 'C'.

Answer

A, B, and C

Answer

C only

Answer

A and C

Question 10

Which TWO of the following are valid methods that can be called on a tuple object? (Choose two.)

Accepted Answer

.index(). The `.index()` method is a built-in tuple method that returns the index of the first occurrence of a specified value. Tuples are immutable sequences, so they support only non-mutating methods like `.index()` and `.count()`, which do not modify the tuple.

Answer

.pop()

Answer

.append()

Answer

.sort()

Question 11

Which TWO of the following are true about function arguments in Python? (Choose two.)

Accepted Answer

Arguments can be passed by position or keyword.. Python allows function arguments to be passed either by position (matching the order of parameters in the function definition) or by keyword (using the parameter name explicitly). This flexibility is a core feature of Python's function call semantics, enabling clearer and more flexible code.

Answer

Default arguments are evaluated each time the function is called.

Answer

*args collects keyword arguments.

Answer

**kwargs collects positional arguments.

Question 12

Which THREE of the following are valid dictionary methods? (Choose three.)

Accepted Answer

.values(). The `.values()` method returns a view object that displays a list of all the values in a dictionary. It is a built-in dictionary method in Python, making option A correct.

Answer

.append()

Answer

.push()

Question 13

Refer to the exhibit. What is the output when the code is executed?

Accepted Answer

2 2 2. The code defines a tuple `t = (0, 1, 2)`. The `for` loop iterates over the tuple, but each iteration prints `t[2]`, which is the third element (index 2) with value 2. Since the value is constant, it prints '2' three times. Hence the output is '2 2 2'.

Answer

0 1 2

Answer

0 0 0

Answer

3 3 3

Question 14

What is the output of the following code?

def greet(name, greeting='Hello'):
    print(greeting, name)

greet('Alice')

Accepted Answer

Hello Alice. The function `greet` has a default parameter `greeting='Hello'`. When called with only one argument (`'Alice'`), the default value is used for `greeting`, so the output is `Hello Alice`. The `print` function outputs both arguments separated by a space.

Answer

Hello

Answer

SyntaxError

Answer

Alice

Question 15

What is the output of the following code?

def test():
    try:
        return 1
    finally:
        return 2

print(test())

Accepted Answer

2. In Python, a `finally` block always executes, and if both `try` and `finally` contain `return` statements, the `return` in `finally` overrides the one in `try`. The function `test()` returns 2, not 1, because the `finally` block's return value is the one that is actually used.

Answer

None

Answer

Error

Answer

1