u/Potential_Fix_5007 You accidentally dodged one of the absolute biggest footguns in Python by doing it inside the body!
If you tried to set it within the round brackets as a default argument—like writing def __init__(self, name, age, marks=[]):—Python does something incredibly sneaky under the hood. It evaluates that default empty list [] exactly once when the script first loads, not every time you create a new student.
Because lists are mutable (changeable), every single student object you create would end up sharing the exact same list instance in memory. If you appended a grade to Alice's marks, it would suddenly and mysteriously show up in Bob's marks too.
By defining self.marks = [] inside the __init__ body, you guarantee that a brand new, isolated list gets allocated in memory every single time a new student is instantiated.
If you ever do want to allow a list to be passed through the round brackets safely, the standard pythonic trick is to default it to None and handle it in the body:
```python
def init(self, name, age, marks=None):
self.name = name
self.age = age
self.marks = marks if marks is not None else []
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u/Potential_Fix_5007 4d ago
self.marks=[]
Is this the right way to create an empty list for an object value or is there a way to set it within the round brackets?
Im a beginner myself and so far i learned if you want to set a default value you donit within the brackets.