Print Class variable that's a list with a Classmethod using __str__?

Question

I'm taking a course in Python, and my task is to print a defined class variable, a list containing all objects of my class, as a formated table using the instance method str

I have no idea how to do this. I did manage to get one object as the output but my output doesn't print all the objects in the list. I tried using a for loop inside the classmethod, but I can still only put one line as the return statement.

Here's my code:

class Person:
    obj = []


    def __init__(self, name, lastname, age):
        self.name = name
        self.lastname = lastname
        self.age = age
        self.obj.append(self)


    def __str__(self):
        print("{:<12} {:<15} {:<10}".format ('Name', 'Last name', 'Age'))
        return "{:<12} {:<15} {:<10}".format (self.name, self.lastname, self.age)

    @classmethod
    def info_people(cls):
        for i in cls.obj:
            str(i).__str__()
        return str(i).__str__()


p1 = Person('Erwin', 'Smith', 34)
p2 = Person('James', 'Porter', 23)
p3 = Person('Madison', 'Stewart', 45)
p4 = Person('Hanna', 'Stark', 14)
p5 = Person('Tina', 'Liu', 6)

print(Person.info_people())



(This was the output)
Name         Last name       Age       
Name         Last name       Age       
Name         Last name       Age
Name         Last name       Age
Name         Last name       Age
Name         Last name       Age
Tina         Liu             6

Answer 1

You can use str.join() and map() functions to construct the string to print. For example:

class Person:
    obj = []

    def __init__(self, name, lastname, age):
        self.name = name
        self.lastname = lastname
        self.age = age
        self.obj.append(self)

    def __str__(self):
        return "{:<12} {:<15} {:<10}".format(self.name, self.lastname, self.age)

    @classmethod
    def info_people(cls):
        out = "{:<12} {:<15} {:<10}\n".format("Name", "Last name", "Age")
        out += "\n".join(map(str, cls.obj))
        return out


p1 = Person("Erwin", "Smith", 34)
p2 = Person("James", "Porter", 23)
p3 = Person("Madison", "Stewart", 45)
p4 = Person("Hanna", "Stark", 14)
p5 = Person("Tina", "Liu", 6)

print(Person.info_people())

Prints:

Name         Last name       Age       
Erwin        Smith           34        
James        Porter          23        
Madison      Stewart         45        
Hanna        Stark           14        
Tina         Liu             6