D522 Python for IT Automation - Set 3 - Part 1

Correct Answer: Managing runtime errors gracefully instead of crashing

Exception handling lets a program respond to runtime errors gracefully rather than terminating abruptly.

Correct Answer: try

The try block contains code that may raise an exception, which the accompanying except block can handle.

Correct Answer: except

Python uses except to catch and handle exceptions raised in the preceding try block.

Correct Answer: finally

The finally block executes regardless of whether an exception occurred, ideal for cleanup such as closing files.

Correct Answer: raise

The raise statement explicitly triggers an exception, optionally with a specific exception type and message.

Correct Answer: ZeroDivisionError

Dividing by zero raises a ZeroDivisionError in Python.

Correct Answer: KeyError

Accessing a key that does not exist in a dictionary raises a KeyError.

Correct Answer: IndexError

Accessing a list position beyond its valid range raises an IndexError.

Correct Answer: ValueError

Trying to convert a non-numeric string to an integer raises a ValueError because the value is invalid for the operation.

Correct Answer: FileNotFoundError

Attempting to open a nonexistent file for reading raises FileNotFoundError.

Correct Answer: To avoid hiding unexpected errors

Catching specific exceptions prevents masking unexpected errors that a broad except would silently swallow, aiding debugging.

Correct Answer: A concise way to build a list from an iterable

A list comprehension creates a list in a single readable expression, such as [x*2 for x in range(5)].

Correct Answer: [0, 1, 2, 3, 4]

This list comprehension collects each value produced by range(5), yielding [0, 1, 2, 3, 4].

Correct Answer: [x for x in data if condition]

A filtering condition is added with an if clause at the end: [x for x in data if condition].

Correct Answer: A concise way to build a dictionary from an iterable

A dictionary comprehension builds a dict in one expression, such as {k: v for k, v in pairs}.

Correct Answer: A small anonymous function defined inline

A lambda is a small anonymous function written inline, such as lambda x: x + 1.

Correct Answer: Applies a function to each item of an iterable

map(function, iterable) applies the function to every element and returns an iterator of the results.

Correct Answer: Keeps items for which a function returns True

filter(function, iterable) returns only the elements for which the function returns True.

Correct Answer: A new sorted list from an iterable

sorted() returns a new sorted list from any iterable, leaving the original unchanged. The list.sort() method sorts in place.

Correct Answer: list.sort()

The list.sort() method sorts the list in place, modifying it directly and returning None.