-
Converts Python iterable objects (
list
,tuple
,set
, etc.) intonamedtuple
objects using a decorator function, so you don't have to rewrite code that already returns iterable objects. -
Sets
namedtuple
attribute names in one of three ways:- Entering attribute names at input prompts (default).
- Manually, by passing an iterable object of attribute names as a keyword argument to the decorated function.
- Setting a keyword argument to automatically generate attribute names.
-
Automatically corrects attribute name entries that would be invalid.
- Python 3.9+
Install via Python pip:
pip install namedtuple-maker
Click to expand and view a decorator example
-
Create an iterable object:
my_favorites = ( 'pizza', 'summer', 'too personal' )
-
Import the
convert_to_namedtuple
decorator function:from namedtuple_maker.namedtuple_maker import named_tuple_converter
-
Create a function that returns an iterable object, and decorate that function with the
convert_to_namedtuple
decorator function:@named_tuple_converter def tuple_to_namedtuple( iterable_input=my_favorites, attribute_names=None ): return iterable_input
-
Call the
tuple_to_namedtuple
function:- Pass an iterable object (the default
my_favorites
object, in this example) to theiterable_input
parameter. - By default, you will receive a prompt to provide an attribute name for each iterable input value.
- You may instead pass a separate iterable object of attribute names to the
attribute_names
parameter.
Option #1 - Enter attribute names using prompts:
# Call the tuple_to_namedtuple function and fill the attribute name prompts my_named_favorites = tuple_to_namedtuple()
Enter an attribute name for the value "pizza": food Enter an attribute name for the value "summer": season Enter an attribute name for the value "too personal": sports team
Option #2 - Pass an iterable object of attribute names to the `attribute_names` parameter:
# Create an iterable object with attribute names my_attributes = ( 'food', 'season', 'sports team' ) # Call the make_named_tuple function and pass in the attribute names my_named_favorites = tuple_to_namedtuple( attribute_names=my_attributes )
- Pass an iterable object (the default
-
Display the resulting
namedtuple
object:print(my_named_favorites)
-
Observe the
print
function output:NamedTuple(food='pizza', season='summer', sports_team='too personal')
Click to expand and view a function usage example
-
Create an iterable object:
my_favorites = ( 'pizza', 'summer', 'too personal' )
-
Import the
make_named_tuple
function:from namedtuple_maker.namedtuple_maker import make_named_tuple
-
Call the
make_named_tuple
function:- Pass an iterable object (the default
my_favorites
object, in this example) to theiterable_input
parameter. - By default, you will receive a prompt to provide an attribute name for each iterable input value.
- You may instead pass a separate iterable object of attribute names to the
attribute_names
parameter.
Option #1 - Enter attribute names using prompts:
# Call the make_named_tuple function and fill the attribute name prompts my_named_favorites = make_named_tuple( iterable_input=my_favorites )
Enter an attribute name for the value "pizza": food Enter an attribute name for the value "summer": season Enter an attribute name for the value "too personal": sports team
Option #2 - Pass an iterable object of attribute names to the `attribute_names` parameter:
# Create an iterable object with attribute names my_attributes = ( 'food', 'season', 'sports team' ) # Call the make_named_tuple function and pass in the attribute names my_named_favorites = make_named_tuple( iterable_input=my_favorites, attribute_names=my_attributes )
- Pass an iterable object (the default
-
Display the resulting
namedtuple
object:print(my_named_favorites)
-
Observe the
print
function output:NamedTuple(food='pizza', season='summer', sports_team='too personal')
Python tuple
objects are great, right? So are list
, set
, and many other iterable Python objects. However, accessing the values of an iterable object using arbitrary index numbers can make code difficult to read. For example, the following list
object stores data about the foods I might eat in a given day:
my_meals = [
'pizza',
'blueberry pancakes',
'granola',
'fruit smoothie',
'rice and beans'
]
Let's say that I want to access values in the list
object named my_food
. I can do that by referencing one or more numeric list indices like this:
print('My Meals')
print('--------')
print(f'Breakfast: {my_meals[1]}\n'
f'Snack: {my_meals[3]}\n'
f'Lunch: {my_meals[4]}')
The resulting output from this code is:
My Meals
--------
Breakfast: blueberry pancakes
Snack: fruit smoothie
Lunch: rice and beans
That works just fine, although it's not terribly intuitive to associate a list
(or tuple
) index number with a certain meal of the day, since this list
doesn't have meals in any particular order. The list index assigned to each meal is arbitrary.
The collections
module in the Python Standard Library includes the namedtuple
function, which allows you to, as the name implies, create tuple-like objects with values that you can reference by name. What does that mean, practically? Well, it means you can access the values in an iterable object by an explicit attribute name that is much more meaningful than an arbitrary index number.
For example, I'll recreate the my_meals
data using a namedtuple
object:
-
First, import the
namedtuple
function from thecollections
module:from collections import namedtuple
-
Next, create a new object type using the
namedtuple
function.- Think of a
namedtuple
object like aclass
object with named attributes, but no methods. - The
typename
parameter is an arbitrary name for the object class. - The
field_names
parameter defines the attribute names for the new object.
Meals = namedtuple( typename='Meals', field_names=[ 'breakfast', 'snack', 'lunch', 'dinner', 'dessert' ] )
- Think of a
-
Now, create an instance of the
Meals
object, and assign the individual foods to each of the named attributes (specified by thefield_names
parameter):my_meals = Meals( breakfast='blueberry pancakes', snack='fruit smoothie', lunch='rice and beans', dinner='pizza', dessert='granola' )
When I want to access or display data from the namedtuple
object named my_meals
, my code will look something like this:
print('My Meals')
print('--------')
print(f'Breakfast: {my_meals.breakfast}\n'
f'Snack: {my_meals.snack}\n'
f'Lunch: {my_meals.lunch}')
The result from this code looks exactly like it did in the first example:
My Meals
--------
Breakfast: blueberry pancakes
Snack: fruit smoothie
Lunch: rice and beans
The key difference between the list
example and the namedtuple
example is, accessing the values in the namedtuple
object uses explicit named attributes (my_meals.lunch
), rather than arbitrary index numbers (my_meals[4]
).
For me, it's much easier to remember that the food I ate for breakfast is accessible as my_foods.breakfast
within a namedtuple
object, than it is to remember an arbitrary list
index value like my_foods[3]
.
The Zen of Python is a great guide for how to write clean and effective Python code. Below is an extract of some of the lines in the output of an import this
command.
The intent of the named-tuplemaker
package is to help Python developers write code that improves compliance with The Zen of Python by making it simple and easy to access iterable object values by explicit attribute names, rather than arbitrary index numbers.
The Zen of Python, by Tim Peters
Beautiful is better than ugly.
Explicit is better than implicit.
Simple is better than complex.
Complex is better than complicated.
...
Readability counts.
...