Exception Handling - Quiz

Complete the statement so that it explicitly throws a ValueError when the age is invalid.

Fill the blank so that the expression checks whether the key 'price' exists in the dictionary product before accessing it.

Complete the statement so that it gets the name of the exception class from the exception object err.

Which statement best describes a Python exception?

What happens if an exception is raised and not handled by any try-except block?

In a basic try-except block, where should you place the code that might fail?

Why is it usually better to catch specific exception types instead of using a bare 'except:'?

How can you catch both ValueError and ZeroDivisionError with the same handler?

When does the else block of a try-except-else-finally structure execute?

What is the primary purpose of the finally block?

Which keyword is used to intentionally trigger an exception in Python?

What is a key benefit of creating custom exception classes?

In exception chaining, what does the 'from' keyword achieve?

Which pair of special methods must a class implement to be used as a context manager with 'with'?

What is a common advantage of using the 'with' statement for file operations?

Order the steps to safely read integers from a text file and handle missing file and bad formatting separately.

Drag and drop to reorder, or use the arrows.

Order the steps to create and use a custom exception for an invalid configuration value.

Drag and drop to reorder, or use the arrows.

What is the output of this code?

1def safe_div(a, b):
2    try:
3        result = a / b
4    except ZeroDivisionError as e:
5        return f"error: {type(e).__name__}"
6    else:
7        return f"ok: {result}"
8
9print(safe_div(6, 3))

What is the output of this code?

1def parse_port(text):
2    try:
3        port = int(text)
4    except ValueError:
5        return "invalid"
6    finally:
7        pass
8    return f"port={port}"
9
10print(parse_port("xyz"))

What is the output of this code?

1def check_positive(n):
2    if n <= 0:
3        raise ValueError("must be positive")
4    return "ok"
5
6try:
7    msg = check_positive(0)
8except ValueError as err:
9    msg = str(err)
10
11print(msg)

What is the output of this code?

1class SilentManager:
2    def __enter__(self):
3        return self
4    def __exit__(self, exc_type, exc_value, tb):
5        return True
6
7try:
8    with SilentManager():
9        raise RuntimeError("boom")
10    print("after")
11except RuntimeError:
12    print("caught")

What is the output of this code?

1def outer():
2    try:
3        int("x")
4    except ValueError as e:
5        raise TypeError("wrapped") from e
6
7try:
8    outer()
9except TypeError as err:
10    print(type(err.__cause__).__name__)

This function should read text from a file and always close it. Identify the bug.

Click on the line(s) that contain the bug.

def read_text(path):

    try:

        f = open(path, "r")

        data = f.read()

        return data

    except FileNotFoundError:

        return "missing"

    finally:

        f.close()

This context manager should suppress only ValueError. Find the bug.

Click on the line(s) that contain the bug.

class SuppressValueError:

    def __enter__(self):

        return self

    def __exit__(self, exc_type, exc_value, tb):

        if isinstance(exc_type, ValueError):

            return True

        return False

Match each exception-related concept to its best description.

Click an item on the left, then click its match on the right. Click a matched item to unmatch.

Match each context manager concept with what it is responsible for.

Click an item on the left, then click its match on the right. Click a matched item to unmatch.

Complete the code to safely convert user input to an integer and log a custom message when the conversion fails.

Complete the custom exception and its use to validate that a configuration timeout is positive.

Complete the context manager so it opens a file for reading and always closes it.

Complete the code so that it re-raises the original exception after adding context.

Click the line that will raise an exception if the key is missing.

Click on the line to select.

config = {"host": "example.com"}

port = config.get("port", 80)

required_host = config["host"]

missing_value = config["timeout"]

print("ready")

Click the line where a finally-style cleanup should occur to always close the connection.

Click on the line to select.

class Connection:

    def close(self):

        print("closed")

conn = Connection()

try:

    print("using connection")

finally:

    conn.close()