![#Python Class Inheritance Syntax Reel by @learninstudy - This output surprises most Python students 😵💫
When you write a = [[0]] * 3, Python does not create three independent lists.
Instead, it creates th](https://image.pictame.com/img/630730236_17855819826614447_8504412477503914307_n.jpg?hash=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)
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LEThis output surprises most Python students 😵💫
When you write a = [[0]] * 3, Python does not create three independent lists.
Instead, it creates three references pointing to the same inner list in memory.
Think of it like this 👇
You didn’t make three notebooks — you made one notebook with three bookmarks
So when you run a[0][0] = 99, you’re modifying that single shared list.
Because all three elements in a point to the same object, the change appears everywhere:
[[99], [99], [99]] ✅
This is why list multiplication with nested lists is dangerous.
It leads to silent bugs in projects, wrong data in ML models, and tricky interview questions.
Correct approach: always use list comprehension when creating nested lists.
Understanding memory references is what separates beginners from real Python developers.
Save this — this detail matters more than syntax
#Python #PythonTricks #PythonEdgeCases #CodingTips #ProgrammingLife
@learninstudy
![#Python Class Inheritance Syntax Reel by @learninstudy - This one tests whether you understand equality vs identity in Python 😏
== checks value equality.
Two empty lists have the same value, so:
[] == []](https://image.pictame.com/img/631274563_1245417380854356_4420608048047673861_n.jpg?hash=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)
