Python Coding Challenge - Question with Answer (ID -210126)

 

Explanation:

Create an empty list

x = []

x is an empty list

Memory-wise, x is a mutable object

Create a single-element tuple

t = (x,)

t is a tuple containing one element

That element is the same list x

Important: the comma , makes it a tuple

Structure so far:

t → ( x )

x → []

 Append the tuple to the list

x.append(t)

You append t inside the list x

Now x contains t

Since t already contains x, this creates a circular reference

Circular structure formed:

t → ( x )

x → [ t ]

Visually:

t

└── x

    └── t

        └── x

            └── ...

Access deeply nested elements

print(len(t[0][0][0]))

Let’s break it down step by step:

🔹 t[0]

First element of tuple t

This is x

🔹 t[0][0]

First element of list x

This is t

🔹 t[0][0][0]

First element of tuple t

This is again x

So:

t[0][0][0] == x

Final Step: len()

len(x)

x contains exactly one element

That element is t

Therefore:

print(len(t[0][0][0]))  # → 1

Final Output

1

Network Engineering with Python: Create Robust, Scalable & Real-World Applications