Homework 8

Homework 8

Total Points:

100 (Correctness and Style) + 3 EC (Checkpoint) + 5 EC (Question 5)

Due Dates (SD time):

● Entire Assignment: Wednesday, Dec 6th, 11:59pm

● Checkpoint (read below): Monday, Dec 4th, 11:59pm

Starter Files

Download hw08.zip. You will find a starter file for the questions of this homework. You cannot import anything to solve the problems except what is given in the starter code.

IMPORTANT: Coding and Docstring Style

This is a reminder that your code style will be graded. Here are a few useful links:

Style Guide Document

Style Guide on Course Website

Style Guide Examples

Testing

At any point of the homework, use the following command to test your work :

>>> python3 -m doctest hw08.py

>>> py -m doctest hw08.py

>>> python -m doctest hw08.py

Also you can call one function at the time using:

>>> python3 -i hw08.py

Checkpoint Submission

Due Date: Monday, December 4th, 11:59pm (SD time)

You can earn up to 3 points extra credit by submitting the checkpoint by the due date above. In the checkpoint submission, you should complete Questions 1 and 2 and submit the hw08.py file to gradescope.

Checkpoint submission is graded by completion, which means you can get full

points if your code can pass some simple sanity check (no tests against edge

cases). Note that in your final submission, you should still submit these questions, and you may modify your implementation if you noticed any errors.

General Notes and Requirements

1. DO NOT IMPORT ANY PACKAGES.

2.  In this homework, you only need to add doctests and docstrings for

Question 4. For other questions, it’s not required to add them, but it’s still recommended to follow the full style guide.

Required Questions

It may seem that the people of Pythonia work and study all the time, but

fortunately, that is not true! There is always time for a fun party to hang out with friends.

Question 1

In this question, we will design a class hierarchy for organizing different parties. Doctests for this question are in the method q1_doctests().

Part 1.2: ArtsAndCrafts

This  is  a subclass of the  ImaginaryParty class.  ArtsAndCrafts will modify the following attributes of the parent class:

Part 1.3: PythoniaGastronomicAdventure

This is a subclass of the ImaginaryParty class. PythoniaGastronomicAdventure will modify the following attributes of the parent class:

Question 2

No party is complete without any activities. You want to start your party off with a bang, and decide to launch some fireworks.

-   To simulate the random chance call random.choice([True,  False]) or random.choice([“successful”, “dud”])

-   The function should return a string:

"The {brand} firework was launched and it was a {successful/dud} launch. It

created {x} decibels of noise."

-   Consider using   random.choice for the random success/dud option. It is imported in the starter already.

-   Testing random inputs is difficult, therefore we recommend you using a

random.seed()

-    With the same seed, it allows us to generate the same sequence of random numbers every time. You can use any seed, as long as you are consistent. See doctests for more examples.

-   Do not forget to update the noise_made for each launch.

Part 2: Class Firecracker

This is a subclass of the Firework class. Firecracker will have the same instance attributes and methods as Firework. The following are the only differences:

-   Firecracker starts with 3 lumens for brightness. Do not repeat yourself, reuse a constructor from a parent class; keyword super is helpful here.

-   Firecracker has a new method calculate_complaints(self), which will set the number of complaints to the right amount, according to the total noise made. There should be a noise complaint for every 250 db of noise made.

-   Return "Received  {x}  new noise complaints." if there is enough noise to warrant a new complaint.

-   Return "No new complaints!" otherwise.

-   Note that noise_made does not get cleared to 0 after receiving a new complaint, and that you will need to update your noise_complaints attribute.

Part 3: RomanCandle

This  is  a  subclass  of  the  Firecracker class.  RomanCandle will  have  the  same instance attributes and methods as Firecracker. The following are the differences:

-   RomanCandle has a  new  instance attribute cops_called which is a boolean that  should  be  set  to  False by  default. Do  not  repeat  yourself,  reuse  a constructor from a parent class; keyword super is helpful here.

-   RomanCandle also  has the method calculate_complaints(self), which you should override (the keyword super can still be used here). The method will function similarly to its parent’s, except for every new noise complaint, there should  be  a  25% chance that the cops are called. If the cops are called, cops_called should be set to True.

-   If the cops are called, you should return “COPS CALLED!!”.

-   There should be a 25% chance the cops are called for each new noise complaint.

-   To  simulate  the  25%  chance  call  random.choice([True,  False, False, False])

-   Do not make more calls to random.choice() than necessary.

-   If  the  cops  aren’t  called,  you  should  return  the  same  output  as Firecracker calculate_complaints(self).

-   Once cops_called is set to True, it should remain True, and the same output   as   Firecracker calculate_complaints(self) should   be returned.

Note: We only provided the base class (Firework) in the starter code, you need to complete the rest of the classes (including the class definitions) yourself.

Exceptions

The noise from the fireworks attracted too much unwanted attention, so you moved the party inside and kept it quiet for the night. You decided to conduct a raffle and host dinner at your party, and you are trying to write a few functions to speed up the process.

Question 3

In this question, you need to fix the implementation of three functions so that they no longer crash. The provided implementation will not work for certain values due to exceptions, thus you need to add a try-except block in each function to deal with this.  You  should  run  the  doctests  to  see  which  exceptions  will  be  thrown.  No additional doctests are needed.

In particular, all you need to do is add a try-except block to handle the potential exception. You should not modify the actual implementation of the given code, and you are not required to add input validations. The provided method descriptions summarize the intended behaviors.

Important Requirements: You will NOT receive credit for the part if you don’t follow.

1.  In each question, you must specify the specific error type(s) in the except block(s). You cannot use

● except:

● except Exception:

● except Exception as e:

2.  Read this article for more detailed explanations of the recommended coding habit.

Part 3.1

Write  a  function  that  generates  raffle  tickets.  The  function   is  supposed  to concatenate every element from letters with every letter from numbers, and return a  list  of  possible  raffle  tickets.  However,  the  current  implementation  crashes because of some bad inputs. If we catch the exception, we should just move on to the next iteration of the loop instead of terminating the entire loop. Do not use pass (for reason read the linked article, you don’t need to log results).

def create_raffle_tix(letters, numbers):

"""

>>> create_raffle_tix(["A", "B", "C"], ["1", 2, "3"]) [ 'A1 ', 'A3 ', 'B1 ', 'B3 ', 'C1 ', 'C3 ']

>>> create_raffle_tix([], [])

[]

>>> create_raffle_tix(["X", None, "Y"], ["1", 2, [3]]) [ 'X1 ', 'Y1 ']

"""

tickets = []

for letter in letters:

for number in numbers:

out.append(str1 + str2)  # add try-except block, specific

to the exception

return tickets

Part 3.2

When sending out invitations to your party, you allowed your guests to upload a file in case they had any special requests, such as allergies. However, some of your guests uploaded corrupted files.

You tried writing a function that is supposed to open each filepath in *filepaths. If we are able to open the file, we should print a  string  '{filepath} opened successfully'. If we are not able to open the file, we should print '{filepath} not found'.  Note  that {filepath} should  be the given file  path string, not the actual string '{filepath}'.

def special_requests(*filepaths):

"""

>>>  special_requests( 'files/vegetarian.txt ',   'files/b.txt ',

'files/c.txt ')

files/vegetarian.txt opened successfully

files/b.txt not found

files/c.txt not found

>>> special_requests( 'random.txt ')

random.txt not found

"""

for filepath in filepaths:

cur_file = open(filepath, "r") # add try-catch block specific

to the exception

cur_file.close()

Part 3.3

You are trying to create table placards for your party, and you asked everyone to provide their first and last name. However, some invitees only provided their first name and some invitees didn’t format their names properly.

This function is trying to concatenate elements from the first_names list with its corresponding elements in the last_names list. In the current implementation, there are two potential errors that may arise. If they are thrown, you should catch them

and print the error types (you can use the type() function). Otherwise, you would just append first_names[i] + last_names[i] to the output list.

def create_placards(first_names, last_names):

"""

>>> create_placards(["cj", "tank", "nico", "dalton"], ["stroud",

"dell"])

[ 'cj stroud ', 'tank dell ']

>>> create_placards(["brock", "george", "brandon"], [None, None])

[]

>>> create_placards([], [])

[]

"""

names = []

for i in range(len(first_names)):

names.append(first_names[i] + “ ” + last_names[i]) # add

try-catch specific to the exception

return names