PCAP Practice Test 21 — 15 Questions

Question 1

Which TWO of the following are true about importing modules using the import statement?

Accepted Answer

The module is executed only once on the first import.. Python caches imported modules in the sys.modules dictionary. When a module is imported for the first time, it is executed and its code is stored; subsequent imports of the same module simply retrieve the cached object from sys.modules without re-executing the module's code. This ensures that module-level initialization runs only once, preventing side effects like repeated resource allocation or redefinition of global variables.

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Relative imports can be used in scripts executed as the main module.

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Importing a module with a different name using 'as' creates a copy of the module.

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Circular imports always cause an ImportError.

Question 2

Which TWO of the following string methods return a boolean value?

Accepted Answer

startswith(). The `startswith()` method returns `True` if the string starts with the specified prefix, otherwise `False`. Similarly, `isalpha()` returns `True` if all characters in the string are alphabetic and there is at least one character, otherwise `False`. Both methods explicitly return a boolean value (`True` or `False`), making them correct choices.

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capitalize()

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format()

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swapcase()

Question 3

Which TWO of the following statements about Python packages are true?

Accepted Answer

A package can contain subpackages.. Python packages are directories that can contain subpackages (nested directories with their own __init__.py files), forming a hierarchical namespace. This allows for organized module grouping, such as `package.subpackage.module`, which is a core feature of Python's module system.

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Packages cannot be imported using the import statement with dot notation.

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An __init__.py file is required in every directory to make it a package.

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A package is a single .py file.

Question 4

Given the string 'Python', what is the result of 'Python'[::-1]?

Accepted Answer

'nohtyP'. The slice notation [::-1] creates a reversed copy of the string by using a step of -1, which traverses the sequence from the end to the beginning. Since strings in Python are immutable sequences of Unicode characters, this operation returns a new string with the characters in reverse order, preserving the original case of each character.

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'nohtyp'

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'NOHYP'

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'Python'

Question 5

Which TWO of the following are built-in Python exceptions?

Accepted Answer

ValueError. ValueError (C) is a built-in Python exception that is raised when a built-in operation or function receives an argument with the correct type but an inappropriate value, such as int('abc'). FileNotFoundError (D) is a built-in exception in Python 3, raised when a file or directory is requested but does not exist, commonly encountered during file I/O operations like open().

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CustomException

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InputError

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FileReadError

Question 6

Which TWO statements about method overriding in Python are correct?

Accepted Answer

The overriding method can call the parent method using super(). The overriding method can call the parent class's version of the method using the built-in `super()` function, which returns a proxy object that delegates method calls to the parent class. This is a fundamental feature of Python's inheritance mechanism, allowing the child method to extend or modify the parent's behavior while still invoking it.

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The overriding method requires explicit use of the @override decorator

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The overriding method must have the exact same parameter list

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Overriding is resolved at compile time

Question 7

Which TWO of the following are valid string methods in Python?

Accepted Answer

capitalize(). `capitalize()` is a built-in string method in Python that returns a copy of the string with its first character capitalized and the rest lowercased. It is part of the standard string methods available for all string objects in Python.

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rotate()

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shuffle()

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reverse()

Question 8

Which THREE of the following are true about Python strings?

Accepted Answer

They support slicing.. Python strings are sequences, and the slicing syntax (e.g., s[start:stop:step]) allows extracting substrings by specifying indices. This works because strings implement the sequence protocol, including __getitem__ with slice objects.

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They are stored as arrays of ASCII characters.

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They are mutable.

Question 9

Which two methods can be used to remove leading whitespace from a string? (Choose two.)

Accepted Answer

s.strip(). `s.strip()` removes both leading and trailing whitespace from the string, including spaces, tabs, and newline characters. This method is commonly used when you need to clean up a string entirely, but it does more than just leading whitespace removal.

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s.split()

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s.chomp()

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s.rstrip()

Question 10

What is the result of 'Python'.find('th')?

Accepted Answer

2. The string method `find()` returns the lowest index where the substring is found. In 'Python', the substring 'th' starts at index 2 (P=0, y=1, t=2, h=3, o=4, n=5). Therefore, the result is 2, making option C correct.

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1

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-1

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0

Question 11

Match each string method to its purpose.

Accepted Answer

upper(): Converts all characters to uppercase.. The correct matches are: .upper() converts to uppercase, .lower() converts to lowercase, .strip() removes leading/trailing whitespace. Common confusions include swapping .split() and .replace(), and confusing .replace() with .upper().

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split(): Replaces all occurrences of a substring with another.

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join(): Splits the string into a list of substrings.

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replace(): Converts all characters to uppercase.

Question 12

Which THREE of the following exception types are subclasses of OSError in Python 3?

Accepted Answer

FileNotFoundError. FileNotFoundError is a direct subclass of OSError, raised when a file or directory is requested but does not exist at the given path. This is part of Python's exception hierarchy for operating system-related errors, specifically for file operations that fail due to missing resources.

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UnicodeError

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EOFError

Question 13

Which TWO of the following string methods return a new string with all characters converted to lowercase? (Select exactly two.)

Accepted Answer

str.lower(). Str.lower(), is correct because it returns a new string with all Unicode characters converted to lowercase according to the current locale's case mapping. Option E, str.casefold(), is correct because it returns a string suitable for case-insensitive comparisons by applying aggressive folding that handles special cases like the German 'ß' (which becomes 'ss'), going beyond simple lowercase conversion.

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str.title()

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str.swapcase()

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str.capitalize()

Question 14

Match each Python module to its purpose.

Accepted Answer

os: Provides a portable way of using operating system dependent functionality.. Common Python standard library modules: os (operating system interface), sys (interpreter access), json (JSON handling), datetime (date and time), re (regular expressions), math (mathematical functions).

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os: Provides access to some variables used or maintained by the interpreter.

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sys: Provides functions for working with dates and times.

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json: Provides support for regular expressions.

Question 15

Which TWO of the following expressions evaluate to `True`? (Select exactly two.)

Accepted Answer

'ab' in 'abc'. The `in` operator checks if the substring 'ab' appears anywhere within the string 'abc'. Since 'abc' contains the consecutive characters 'a' followed by 'b', the expression evaluates to True.

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'x' in 'abc'

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'ab' not in 'abc'

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'abc' in 'ab'