Python tuple() Function

The tuple() function in Python is used to create an immutable ordered collection of elements called a tuple. Tuples are similar to lists, but they cannot be changed after creation.

Syntax

tuple(iterable)

Parameters:

• iterable – (Optional) Any iterable like a list, string, set, or dictionary.

Returns:

• A new tuple containing elements from the given iterable.

Example 1: Convert a List to Tuple

my_list = [1, 2, 3]
result = tuple(my_list)
print(result)

(1, 2, 3)

Example 2: Convert a String to Tuple

text = "abc"
result = tuple(text)
print(result)

('a', 'b', 'c')

Example 3: Using tuple() with a Dictionary

my_dict = {'a': 1, 'b': 2}
result = tuple(my_dict)
print(result)

('a', 'b')

Note: Only the keys are included in the resulting tuple.

Example 4: Create an Empty Tuple

empty = tuple()
print(empty)

()

Why Use Tuples?

• Immutability: Tuples can’t be modified, making them useful for fixed data.
• Performance: Faster than lists for read-only data.
• Hashable: Tuples can be used as dictionary keys or set elements (if they only contain hashable items).

Common Mistakes

• Writing tuple = () and then using tuple() will cause an error (do not overwrite built-ins).
• Confusing parentheses () with tuple creation – remember, () alone is empty tuple, (5) is just a number, use (5,) to create a one-element tuple.

Interview Tip

In interviews, tuples are often used when returning multiple values from functions, or for storing coordinates, RGB values, etc.

Summary

• tuple() converts an iterable into a tuple.
• Tuples are immutable – you can't change them after creation.
• Empty tuple: tuple(); one-item tuple: (item,).

Practice Problem

Convert the following list into a tuple, and then try to change one value. What happens?

numbers = [10, 20, 30]
t = tuple(numbers)
print(t)
# Try this:
# t[0] = 99  # What error do you get?