PCPP1 Library Modules — 25 Questions

Question 1

You are writing data to a CSV file using csv.writer. You want to ensure that row delimiters are handled correctly across different operating systems. What should you set the 'lineterminator' parameter to?

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

lineterminator='
'. The lineterminator parameter should be explicitly set to '
' for cross-platform compatibility.

Answer

lineterminator='
'

Answer

lineterminator=os.linesep

Answer

lineterminator='\r'

Question 2

Which THREE of the following are valid parsing modes for the XML module?

Accepted Answer

xml.etree.ElementTree.XMLParser(). XML can be parsed via strings, files, or incremental/streamed methods.

Answer

xml.etree.ElementTree.read()

Answer

xml.etree.ElementTree.load_xml()

Question 3

When using sqlite3.Row, what is the primary benefit over using a standard tuple?

Accepted Answer

It provides dictionary-like access to columns by name.. sqlite3.Row allows accessing column values by name (string keys) instead of just numerical indices.

Answer

It automatically commits transactions.

Answer

It is faster to execute.

Answer

It supports multi-threading natively.

Question 4

You are using configparser.ConfigParser to read a configuration file. You have a file where option names are case-sensitive. How do you ensure the parser respects this casing?

Accepted Answer

parser.optionxform = lambda x: x. By default, ConfigParser converts keys to lowercase. You must override the optionxform method of the parser instance.

Answer

parser = ConfigParser(case_sensitive=True)

Answer

parser.set_case(True)

Answer

parser.read(file, case='preserve')

Question 5

You are processing a CSV file using csv.DictReader. If your input file lacks a header row, how do you provide the field names?

Accepted Answer

csv.DictReader(f, fieldnames=['a', 'b']). You pass the 'fieldnames' argument to the constructor to define the headers explicitly.

Answer

csv.DictReader(f, headers=['a', 'b'])

Answer

csv.DictReader(f).map(['a', 'b'])

Answer

csv.DictReader(f, columns=['a', 'b'])

Question 6

When parsing an XML document using xml.etree.ElementTree, you want to find all 'item' tags that are immediate children of the root element. Which method is most efficient for this?

Accepted Answer

root.findall('item'). The findall() method with a direct path is the standard way to retrieve specific children.

Answer

root.iter('item')

Answer

root.find('item')

Answer

root.get('item')

Question 7

Which method in the xml.dom.minidom module is used to retrieve the value of a specific attribute of an element?

Accepted Answer

element.getAttribute('attr_name'). The getAttribute() method is used to retrieve the value of an attribute by its name.

Answer

element.attr('attr_name')

Answer

element.getAttributeNode('attr_name').value

Answer

element.value('attr_name')

Answer

element['attr_name']

Question 8

You need to configure the logging module to capture logs from multiple modules while ensuring that logs from third-party libraries (e.g., 'urllib3') are only captured at the WARNING level. How do you set this?

Accepted Answer

logging.getLogger('urllib3').setLevel(logging.WARNING). You can configure individual loggers using getLogger() and setting their specific level attribute.

Answer

logging.config.dictConfig({'urllib3': 'WARNING'})

Answer

logging.basicConfig(level=logging.WARNING)

Answer

logging.setLevel('urllib3', logging.WARNING)

Question 9

You are using the sqlite3 module to manage a database. You need to ensure that database changes are permanently saved even if your script terminates unexpectedly. Which method should you call after an INSERT operation?

Accepted Answer

connection.commit(). The commit() method on a connection object is required to save changes permanently in sqlite3.

Answer

connection.save()

Answer

cursor.flush()

Answer

connection.close()

Question 10

When using configparser, how do you retrieve a value as a boolean?

Accepted Answer

parser.getboolean('section', 'option'). The getboolean() method converts common truthy/falsy values automatically.

Answer

parser.get('section', 'option', type=bool)

Answer

parser.get_bool('section', 'option')

Answer

bool(parser.get('section', 'option'))

Question 11

In the csv module, how do you specify that the CSV file uses a semicolon (;) as a delimiter?

Accepted Answer

csv.reader(f, delimiter=';'). The delimiter parameter in the csv.reader or csv.writer function is used for this purpose.

Answer

csv.reader(f, char=';')

Answer

csv.reader(f, sep=';')

Answer

csv.reader(f, quotechar=';')

Question 12

Which class in xml.etree.ElementTree should you use to parse an XML file from a file object?

Accepted Answer

ElementTree.parse(). The parse() function is the standard way to read XML from a file object.

Answer

ElementTree.XML()

Answer

ElementTree.load()

Answer

ElementTree.read()

Question 13

You are logging events with custom levels. How do you add a custom level 'TRACE' (value 5) to the logging module?

Accepted Answer

logging.addLevelName(5, 'TRACE'). You use logging.addLevelName() to associate a numerical value with a level name.

Answer

logging.TRACE = 5

Answer

logging.setLevel('TRACE', 5)

Answer

logging.define_level('TRACE', 5)

Question 14

When executing a SQL query with parameters in sqlite3, why should you use placeholders (e.g., ?) rather than f-strings?

Accepted Answer

It prevents SQL injection vulnerabilities.. Using placeholders prevents SQL injection attacks and allows the library to handle type conversions.

Answer

It is required for SELECT queries only.

Answer

It enables automatic commit behavior.

Answer

It is faster to execute.

Question 15

You are configuring logging using a dictConfig. You want to send logs to a RotatingFileHandler. Which key must you define in the 'handlers' section?

Accepted Answer

class. The 'class' key is required to specify the handler type, e.g., 'logging.handlers.RotatingFileHandler'.

Answer

destination

Answer

type

Answer

handler_type

Question 16

When using configparser, what happens if you attempt to read a configuration file that does not exist using the read() method?

Accepted Answer

It returns an empty list.. The read() method returns an empty list and does not raise an exception.

Answer

It raises a FileNotFoundError.

Answer

It raises a configparser.Error.

Answer

It creates an empty configuration object.

Question 17

What is the result of using '?' as a placeholder in sqlite3 for a parameter that is a Python list?

Accepted Answer

It raises a ProgrammingError.. sqlite3 does not automatically expand lists; you must use a tuple of values or construct the SQL dynamically.

Answer

It automatically converts the list to a comma-separated string.

Answer

It works as expected.

Answer

It only takes the first element of the list.

Question 18

In xml.etree.ElementTree, what is the difference between find() and findall() when used with XPath support?

Accepted Answer

findall() returns a list, find() returns a single element.. findall() supports full XPath syntax, whereas find() supports a more limited subset.

Answer

find() is faster for large trees.

Answer

findall() requires an iterator.

Answer

findall() is recursive, find() is not.

Question 19

When using configparser, how do you handle multiline values?

Accepted Answer

Indent the subsequent lines.. You indent lines following the initial line within the option.

Answer

Use a backslash at the end of each line.

Answer

Wrap them in triple quotes ('''...''').

Answer

Use the '
' escape character.

Question 20

When parsing XML with ElementTree, how do you retrieve the text content of an element?

Accepted Answer

element.text. The .text attribute of the Element object holds the text content.

Answer

element.content

Answer

element.value

Answer

element.get_text()