Python review

Which is the special symbol used in python to add comments?

#

Please select the valid single line comment in Python.

# comment

Which of the following lines represents a valid comment?

# print('Content')

Whats is the proper shebang to indicate the script is using Python version 3?

#!/usr/bin/env python3

The open() function opens a file in text format by default. Which mode opens the file in binary format for reading?

'rb'

Which of the following modes is most suitable for writing a binary file in Python?

'wb'

Which one of the following is the correct extension of the Python file?

.py

What is the value returned from this code? print(type(True))

<class 'bool'>

What is the value returned from this code? print(type(4))

<class 'int'>

What is the value returned from this code? print(type('?'))

<class 'str'>

Which of the following statements are true?

A compiler scans the entire source code file and translates the whole of it into machine code at once An interpreter translates one statement of the source code at a time into machine code Compiled code tends to execute faster than interpreted code

A programmer has created a class to represent Employees, and each employee has a unique name, role and ID number. The programmer also wants to create a special method to overload the len() method such that every Employee instance will return the seniority in the company. What is best to use for this situation?

A dunder method

Consider a program that has a module that provides a framework of sorts to short declarative one-file scripts that writes. Which of the following words is suitable for describing the previous program.

A module callback

Which of the following casts could result in a run time error?

A string cast as an int

Which of the following best describes the built-in tuple class?

An immutable, iterable collection able to hold any type

Which collection structure stores items in key value pairs?

Dictionary

What are Runtime Errors in Python? (Select all that apply)

Errors that show up when the script is attempting to perform operations on data of the wrong type Errors that occur because of misspelled or incorrectly capitalized variable and function names

How is called a programming paradigm where programs are constructed by applying and composing functions?

Functional Programming

Which of the following is used to define a block of code in Python?

Indentation

Which collection structure allows items that are ordered and changeable and contain duplicate values?

List

Suggest why a program may be broken down into individual functions

Maintainability. Smaller, simpler functions are easier to maintain. Debugability. It's easier to debug simple functions than complex ones. Reuseability. Encourages code reuse by moving common operations to a separate function.

Consider a program which manages its use by more than one user at a time and to even manage multiple requests by the same user without having to have multiple copies of the programming running in the computer. Which of the following words is suitable for describing the previous program.

Multithreading

"a"

Open a text file for appending text

"r"

Open a text file for reading text

"w"

Open a text file for writing text

Which of the following statements are true?

Python code is structured and indented blocks must be used

The pip command line utility allows the developer to install ________?

Python packages

Which collection structure stores items that are unordered and unindexed?

Set

A programmer tries to run the following code. What error is likely to be raised in this instance?

SyntaxError

What is the purpose of the break statement in Python?

Terminate the loop and transfer control to the statement following the loop

When creating a text file using the built-in open() function with 'a mode', what will occur if a file is written to a directory which contains a file having the same name?

The file is appended to, with the original contents saved

Which collection structure allows items that are ordered and unchangeable?

Tuple

A programmer accidentally attempts convert the type of an object and receives the next error: 'int() cannot convert 'dog' into an integer'. What error was likely raised in this instance?

ValueError

"x"

Verifies the file does not exist

When defining an object with a class, what function is used to establish values of an instance?

__init__()

Which of the following modes of file reading would be most appropriate for a program designed to update the contents of a .txt file without making any new deletion to the file.

a

Which of the following best describes 're'? 're' (regular expression) provides regular expression matching operations similar to those found in Perl.

a module

Which of the following best describes 'sklearn'? 'sklearn' (scikit-learn) provides Machine Learning operations and it contains simple and efficient tools for predictive data analysis

a package

Which of the following shows the correct way to initialize a single dimension array?

arr = ['Kan', 'Ryne', 'Em'] arr = []

Which of the following shows the correct way to initialize a multidimensional array?

arr = [] arr = [[]]

How many except statements can a try-except block have?

at least one

Which statement would indicate that the D3Point class inherits characteristics from the Point class?

class D3Point(Point):

A data structure where the type or the class is less important than the methods it defines is known as what?

duck-typed

Which of the following methods allows multiple items from a string to be added as individual elements to an existing list? Use the example below for context

extend()

Which statement would assign the input.txt file to the handler fin?

fin = open("input.txt", "r")

Which statement would read the entire file contents?

fin.read()

A data structure that can't be changed after its creation is known as _____?

immutable

Assume you have written your Python code in a separate file named 'myfunctions.py'. Which of the following statements shows the correct syntax for adding it to your new Python script so the code can be used?

import myfunctions

An operation that modifies a variable without making a copy is known as ....

in-place operation

Which of the following methods allows to insert a specified value on a specified position?

insert()

What does the "continue" Statement in Python do?

it does not break the loop it terminates the execution of statements while iterating the loop

Which list function returns the number of items contained in the list?

len(listname)

Consider the following piece of code. Which of the following is true? from sklearn.linear_model import LinearRegression

linear_model is a module of sklearn package

Which code would allocate and initialize a list of 10 integers?

nlist = [0] * 10

Which of the following keywords is able to turn a False into a True and is also known as a 'logical inverter'

not

A developer wants to read a text file but he is unsure if the file exists in the current directory. Suggest a suitable module that could be used to check for the presence of the file in the current working directory.

os module

You are coding a tip calculator. The user must enter a price. Select the line of code that will make your program work whether the user enters whole numbers (for example, 10) or numbers that include decimals (for example, 30.99).

price = float(input("Enter the price"))

How to output the string "Hello" in Python?

print("Hello")

A programmer wants to match a specific string using a regular expression. What would be most appropriate to match the following string? 'Hello NAME'. The 'NAME' can be any 4 letter name containing only letters, such as 'Hi Alex', or 'Hi John'

r'Hi \w{4}'

Which line of code inserted in the program will add a random item from the list each time the loop runs?

rand_item = random.choice(option_list)

Which methods would be used to generate random numbers in Python?

random.uniform() random.randint() random.random()

A programmer wants to use simple and efficient tools for predictive data analysis that are used for Machine Learning. Suggest a suitable module or package that could be used to check for this task.

scikit-learn

A programmer wants to use various functions and variables that are used to manipulate different parts of the Python runtime environment. Suggest a suitable module that could be used to check for this task.

sys module

Which of the following best describes the built-in set class?

unordered collection, iterable, mutable and has no duplicate elements

Which of the following modes of file writing would be most appropriate for a program designed to update the contents of a .txt file and to overwrite the entire file if the file contains any data.

w