Python Coding Challenge - Question with Answer (ID -020226)

 

Step 1: List creation

lst = [1, 2, 3]

A list with three integers.

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Step 2: Loop starts

for i in lst:

The loop runs 3 times:

• 1st time → i = 1

• 2nd time → i = 2

• 3rd time → i = 3

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Step 3: The tricky part

if i is 2:

Here:

• is checks identity (memory location)

• == checks value

So this line means:

“Is i pointing to the exact same object in memory as 2?”

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Why does it print "Two"?

Python caches small integers from -5 to 256.
So every time you write 2, Python uses the same memory object.

That means:

i is 2   → True

So it prints:

Two

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Important Interview Rule ⚠️

This works by accident, not by design.

Correct way:

if i == 2:

Because:

• == → always reliable

• is → only for None, True, False

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Memory proof (advanced)

print(id(2))
print(id(i))

Both IDs are same → same object.

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Final takeaway for your students (CLCODING):

Never use is for number or string comparison.
Use it only for None or singleton objects.

This question is famous in Python interviews because it tests real understanding, not syntax