Question

There are design imperfections with this code. relating to encapsulation (in terms of the class), and something to do with how age is calculated being rigid (in terms of it only works for 2019, and will break next year). Improve the design of this code, and add a short comment or two up the top explaining what you've done and why.

code:

class Student:
def __init__(self, firstName, lastName, birth_year):
self.name = firstName + " " + lastName
self.birth_year = birth_year

if __name__ == '__main__':
s = Student("Rob", "Everest", 1961)
years_old = 2019 - s.birth_year
print(f"{s.name} is {years_old} old")

Answer 1

thanks for the question, here is the updated code with comments.

=======================================================================

# datetime module to get the current year
from datetime import datetime


class Student():

    def __init__(self,firstName,lastName,birth_Year):
        # make the instance variables as private
        # so that they cannot be accessed directly
        # we make them private by appending with two underscores
        # for accessing the values of the isntance variable we provide accessor functions
        self.__name = firstName+" "+lastName
        self.__birth_year = birth_Year

    def getName(self):
        return self.__name

    def getBirthYear(self):
        return self.__birth_year

if __name__ == '__main__':

    s = Student('Rob','Everest',1961)
    # find the current year using the below line of code
    current_year =datetime.now().year

    # use accessor functions to get the value of birth year
    years_old = current_year-s.getBirthYear()
    # use accessor functions to get the value of name
    print('{} is {} old'.format(s.getName(),years_old))

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