Free Practice Questions for Python Institute PCPP-32-101 Exam

A socket object is usually created using the socket() constructor provided by the socket module in Python. The correct invocation is socket.socket(socket_domain, socket_type). This creates a new socket object with the specified socket domain and type.

The correct answer is D. The code is responsible for the support of the inequality operator i.e. i != j. In the given code snippet, the __ne__ method is a special method that overrides the behavior of the inequality operator != for instances of the MyClass class. When the inequality operator is used to compare two instances of MyClass, the __ne__ method is called to determine whether the two instances are unequal.

Answer: A. Deserialization is the process of converting data that has been serialized or encoded in a specific format, back into its original form as an object or a data structure in memory. In Python, this typically involves creating Python objects based on sequences of bytes that have been serialized using a protocol such as JSON, Pickle, or YAML.

For example, if you have a Python object my_obj and you want to serialize it to a JSON string, you might do something like this:

importjson

serialized_obj = json.dumps(my_obj)

To deserialize the JSON string back into a Python object, you would use the json.loads() method:

deserialized_obj = json.loads(serialized_obj)

This would convert the JSON string back into its original Python object form.

According to PEP 8 recommendations, the two best options are Option B and Option D.

Option B follows PEP 8’s suggestion that all lines should be limited to 79 characters and for longer blocks of text like docstrings or comments, the length should be limited to 72 characters1. Option D follows PEP 8’s conventions for writing good documentation strings (a.k.a. “docstrings”) which are immortalized in PEP 257. It suggests writing docstrings for all public modules, functions, classes, and methods2.

The socket.gaierror exception is raised when an address-related error caused by the getaddrinfo() and getnameinfo() functions occurs. These functions are used to translate hostnames to IP addresses and vice versa, and the gaierror exception is raised if they fail to perform this translation.

 The true statement about the __name__ attribute is D. name is a special attribute, which is inherent for classes, and it contains the name of a class. The __name__ attribute is a special attribute of classes that contains the name of the class as a string.

The __name__ attribute is a special attribute in Python that is available for all classes, and it contains the name of the class as a string. The __name__ attribute can be accessed from both the class and its instances using the dot notation.

The given code snippet demonstrates the concept of encapsulation in object-oriented programming. Encapsulation refers to the practice of keeping the internal state and behavior of an object hidden from the outside world and providing a public interface for interacting with the object. In the given code snippet, the __init__ and get_balance methods provide a public interface for interacting with instances of the BankAccount class, while the __balance attribute is kept hidden from the outside world by using a double underscore prefix.

A. In the context of TCP/IP networks, the communication side that initiates a connection is called the client, whereas the side that answers the client is called the server.

This statement is true because TCP/IP networks use a client-server model to establish connection-oriented communications. The client is the device or application that requests a service or resource from another device or application, which is called the server. The server responds to the client’s request and provides the service or resource.For example, when you browse a website using a web browser, the browser acts as a client and sends a request to the web server that hosts the website. The web server acts as a server and sends back the requested web page to the browser1.

B. Connectionless communications are usually built on top of TCP.

This statement is false because TCP (Transmission Control Protocol) is a connection-oriented protocol that requires establishing and terminating a connection before and after sending data. Connectionless communications are usually built on top of UDP (User Datagram Protocol), which is a connectionless protocol that does not require any connection setup or teardown. UDP simply sends data packets to the destination without checking if they are received or not2.

C. Using walkie-talkies is an example of a connection-oriented communication.

This statement is false because using walkie-talkies is an example of a connectionless communication. Walkie-talkies do not establish a dedicated channel or connection between the sender and receiver before transmitting data. They simply broadcast data over a shared frequency without ensuring that the receiver is ready or available to receive it. The sender does not know if the receiver has received the data or not3.

D. A phone call is an example of a connection-oriented communication.

This statement is true because a phone call is an example of a connection-oriented communication. A phone call requires setting up a circuit or connection between the caller and callee before exchanging voice data. The caller and callee can hear each other’s voice and know if they are connected or not. The phone call also requires terminating the connection when the conversation is over4.

References:

1: https://www.techtarget.com/searchnetworking/definition/client-server  2: https://www.javatpoint.com/connection-oriented-vs-connectionless-service  3: https://en.wikipedia.org/wiki/Walkie-talkie  4: https://en.wikipedia.org/wiki/Telephone_call

A is true because in the context of TCP/IP networks, the communication side that initiates a connection is called the client, and the side that answers the client is called the server. This is the basis for establishing a connection-oriented communication.

D is true because a phone call is an example of a connection-oriented communication. Like TCP/IP, a phone call establishes a connection between two devices (in this case, two phones) before communication can occur.

A is true because in the context of TCP/IP networks, the communication side that initiates a connection is called the client, and the side that answers the client is called the server. This is the basis for establishing a connection-oriented communication.

D is true because a phone call is an example of a connection-oriented communication. Like TCP/IP, a phone call establishes a connection between two devices (in this case, two phones) before communication can occur.

B is false because connectionless communications are usually built on top of UDP, not TCP. UDP is a connectionless protocol that does not establish a connection before sending data.

C is false because using walkie-talkies is an example of a connectionless communication. Walkie-talkies do not establish a connection before communication begins, and messages are simply broadcasted to all devices within range.

Here is a sample code in Python using the socket module to create a TCP server and client to demonstrate the connection-oriented communication:

Server-side code:

importsocket

HOST ='127.0.0.1'

PORT =8080

with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:

s.bind((HOST, PORT))

s.listen()

conn, addr = s.accept()

with conn:

print('Connected by', addr)

whileTrue:

data = conn.recv(1024)

ifnotdata:

break

conn.sendall(data)

Client-side code:

importsocket

HOST ='127.0.0.1'

PORT =8080

with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:

s.connect((HOST, PORT))

s.sendall(b'Hello, world')

data = s.recv(1024)

print('Received',repr(data))

The server listens for incoming connections on port 8080, and when a connection is established, it prints the address of the client that has connected. The server then continuously receives data from the client and sends it back to the client until the connection is closed.

The client establishes a connection with the server and sends the message "Hello, world" encoded as bytes. It then waits for a response from the server and prints the data it receives.

The two true statements related to PEP 8 programming recommendations for code writing are Option B and Option D.

Option B is true because PEP 8 recommends making object type comparisons using the isinstance() method instead of comparing types directly 1.

Option D is true because PEP 8 recommends not writing string literals that rely on significant trailing whitespaces as they may be visually indistinguishable, and certain editors may trim them 1.