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Python Object-Oriented Python Instant Objects Method Interactivity

Posted by sachin prasad
sachin prasad
1,564 Points

Getting this error Exception: argument of type 'NoneType' is not iterable Not sure whats wrong here.

What am i doing wrong here? Exception: argument of type 'NoneType' is not iterable

I wish there was more explanation on when to use self and when not to use self.

first_class.py 
class Student:
    name = "Sachin"

    def praise(self):
        return "You inspire me, {}".format(self.name)

    def reassurance(self):
        return "Chin up, {}. You'll get it next time!".format(self.name)

    def feedback(self, grade):
        if grade > 50:
            self.praise()
        else:
            self.reassurance()

1 Answer

Micah Hack
Micah Hack
12,902 Points
Micah Hack
Micah Hack
12,902 Points

Hello Sachin,

You're very close. You have the right idea. The self in your method calls is correct. The purpose of self is tell your class where to find the method you are calling. Your feedback method is calling praise and reassurance, but you have not specified it to do anything with the results.

I believe you are receiving the "'NoneType' object is not iterable error", because the value of the data is "None" due to it not being returned to the method.

In short all you need to do is "return" the result of the praise method as well as "return" the reassurance method's result.

I hope this helps. This is my first time attempting to answer a question, lol!

sachin prasad
sachin prasad
1,564 Points

Thank you Micha, That helped and fixed my issue.