How to Use namedtuple in Python: Syntax and Examples

Use namedtuple from the collections module to create simple classes with named fields. Define a namedtuple by giving it a type name and field names, then create instances with those fields accessible by name.

Syntax

The namedtuple function creates a new subclass of tuple with named fields. You provide a type name and a list of field names as strings.

• Type name: The name of the new tuple class.
• Field names: A list or space/comma-separated string of field names.

python

from collections import namedtuple

Point = namedtuple('Point', ['x', 'y'])

# Create an instance
p = Point(10, 20)

# Access fields
print(p.x)  # 10
print(p.y)  # 20

Output

10
20

Example

This example shows how to define a namedtuple Car with fields make, model, and year. It creates an instance and prints each field by name.

python

from collections import namedtuple

Car = namedtuple('Car', 'make model year')
my_car = Car(make='Toyota', model='Corolla', year=2020)

print(f"Make: {my_car.make}")
print(f"Model: {my_car.model}")
print(f"Year: {my_car.year}")

Output

Make: Toyota
Model: Corolla
Year: 2020

Common Pitfalls

Common mistakes include:

• Using invalid field names (like keywords or starting with numbers).
• Trying to modify fields after creation (namedtuples are immutable).
• Confusing the namedtuple type with an instance.

Always use valid Python identifiers for field names and remember namedtuples behave like tuples, so you cannot change fields once set.

python

from collections import namedtuple

# Wrong: field name '1st' starts with a number
# Person = namedtuple('Person', ['name', '1st'])  # This will raise an error

# Correct:
Person = namedtuple('Person', ['name', 'first'])
p = Person('Alice', 'Smith')

# Trying to change a field (will raise AttributeError)
try:
    p.name = 'Bob'
except AttributeError as e:
    print(e)

Output

can't set attribute

Quick Reference

Feature	Description
Create namedtuple	namedtuple('TypeName', ['field1', 'field2'])
Access field	instance.field1
Immutable	Fields cannot be changed after creation
Supports tuple features	Indexing, unpacking, iteration
Convert to dict	instance._asdict()

Key Takeaways

Use namedtuple to create simple, readable, immutable data objects with named fields.

Define a namedtuple by specifying a type name and valid field names.

Access fields by name for clarity instead of using tuple indexes.

Namedtuples are immutable; you cannot change fields after creation.

Use _asdict() method to convert namedtuple instances to dictionaries.