Python Coding Challenge - Question with Answer (ID -290326)

 

Explanation:

🔹 1. Creating an Empty Dictionary

d = {}

A dictionary d is created.

Dictionaries store data in key → value pairs.

Keys must be hashable (immutable types).

🔹 2. Creating a List as Key

key = [1, 2]

A list [1, 2] is created.

⚠️ Lists are mutable (can be changed later).

🔹 3. Assigning List as Dictionary Key

d[key] = "value"

Here Python tries to use the list as a dictionary key.

🚨 Problem:

Dictionary keys must be:

Immutable

Hashable

Lists are:

Mutable ❌

Not hashable ❌

👉 So Python raises an error:

TypeError: unhashable type: 'list'

🔹 4. Print Statement

print(d)

This line never executes because the program crashes earlier.

❗ Final Output

Error

TypeError: unhashable type: 'list'

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