CSc 110 Assignment 10

Classes and instance data

Learning Outcomes:

When you have completed this assignment, you should understand: 

• Write instance methods

• Write methods that operate on objects and lists of objects

Getting started

1. Download the starter files provided called assignment10.py, date.py and pet.py and open them in 

your Wing editor

2. Download the provided input csv files to the same directory as the starter files

3. We cannot upload an empty file to BrightSpace so you will need to create an empty file in the same directory 

as your starter files and name it empty.csv

4. Design the methods/functions according to the specifications in the documentation provided in the starter file

and using the further explanation given in the Method/Function Specifications section below. 

Submission

1. Double check your file before submission to avoid a zero grade for your submission for issues described in 

the Grading section of this document:

a. Open and run assignment10.py, date.py and pet.py in your Wing. 

You should see no errors and no output after the shell prompt. 

If there are errors, you must fix them before submitting. 

If there is output printed to the shell, find and remove any top-level print statements and/or top level 

function calls.

b. At the shell prompt in Wing (>>>) type the following import assignment10

You should see no errors and no output after the shell prompt. 

If there are errors, you must fix them before submitting.

If there is output printed to the shell, find and remove any top-level print statements and/or top level 

function calls.

c. At the shell prompt in Wing (>>>), make calls to the required functions to ensure you have named 

them correctly. Ensure the function is exhibiting the expected behaviour when called and does not 

contain any unexpected output. You should be able to make calls to the following methods/functions

from your shell prompt:

i. is_after (method in Date class)

ii. == to compare 2 pet instances (__eq__ in Pet class)

iii. read_file

iv. find_pet

v. get_all_of_species

vi. get_latest_birthdate

vii. get_youngest_pets

d. Ensure you have closed any files that you have opened!

2. Upload your assignment10.py, date.py and pet.py to BrightSpace

Reminder: Your code is to be designed and written by only you and not to be shared with anyone else. See the 

Course Outline for details explaining the policies on Academic Integrity. Submissions that violate the Academic 

Integrity policy will be forwarded directly to the Computer Science Academic Integrity Committee. 

Grading:

• Late submissions will be given a zero grade. • The files you submit must be named assignment10.py, date.py and pet.py

The filenames must be EXACT for them to work with our grading scripts. Errors in the filenames will 

result in a zero grade. 

Example mistakes often made by students include but are not limited to: spelling errors, different case 

letters, space characters and incorrect extension (not using .py) 

• Your function names and the order of your function arguments must match EXACTLY as specified in 

this document or you will be given a zero grade. Use the example tests we give you to ensure your 

function header is correct.

• Your submission must not contain any print statements that are not required in the specification or any 

top-level calls to functions. This unexpected code can cause the automated tester to crash and will result 

in a zero grade. • We will do spot-check grading in this course. That is, all submissions are graded BUT only a subset of 

your code might be graded. You will not know which portions of the code will be graded, so all of your 

code must be complete and adhere to specifications to receive marks.

• Your code must run without errors with Python 3. If you tested your configuration with setup.py file this 

would have verified you are using Python 3. Code that generates errors cannot be tested and will be given 

a zero grade. 

Marks will be awarded for correctness, considering:

• the function signature matches the description given (has the name and arguments EXACTLY as 

specified)

• the function has the expected behaviour

and for code quality according to software engineering properties such as:

• documentation in docstring format: type hints, purpose, examples

• Test coverage – examples within the function docstring cover all boundary cases of all conditions within 

your function

• readability

o use of whitespace

o splitting complex computation or long statements across multiple lines 

• meaningful variable names o lower case, starting with an alpha-character

• proper use of constants (avoid magic numbers)

o defined above all function definitions

o in UPPERCASE

• use of code constructs (functions, variables) to: o eliminate redundant code and redundant computation

o make complex code easier to read

Method/Function Specifications:

Familiarize yourself with the code provided in date.py and pet.py You will design a method in each of 

date.py and pet.py according to the specification given below. 

In the given specifications we have omitted examples as coming up with those examples is part of the problem 

solving process. Feel free to use the forum to clarify any ambiguities that you encounter in the specifications 

when trying to establish your examples. Don’t forget your FULL documentation.

1. Within date.py implement a method called is_after that takes as arguments the hidden reference to the 

Date instance itself (self) and an additional instance of a date (other).

The function should return True if the date represented by self is after that represented by other in the calendar 

and False otherwise.

2. Within pet.py implement the __eq__ method so that it overrides the existing implementation 

automatically inherited. When your implementation is complete, when an instance of a Pet is compared to 

another Pet using == it should return True if the name, species and birthdate of the two Pet instances are 

the same and return False otherwise. 

Note: the header of this function must have the correct function name and number of arguments for this 

overriding to work. See date.py for an example of this.

3. Within assignment10.py, complete the implementation for the functions marked TODO according to the 

documentation given. You must understand how to call the instance methods within the Date and Pet classes 

in order to complete these function designs.