Python's namedtuple is a powerful tool that allows you to create lightweight classes that are similar to tuples, but with named fields. This can be useful in a variety of situations where you need to represent a collection of related values, such as a record from a database, a point in a Cartesian coordinate system, or a user account.
The namedtuple function is part of the collections module in Python's standard library, and can be used to create custom tuple subclasses with named fields. Here's a simple example:
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from collections import namedtuple
# Define a new named tuple class
Person = namedtuple('Person', ['name', 'age', 'gender'])
# Create a new instance of the named tuple
person1 = Person(name='Alice', age=25, gender='female')
person2 = Person(name='Amir', age=40, gender='male')
# Access the fields by name
print(person1.name) # Output: Alice
print(person1.age) # Output: 25
print(person1.gender) # Output: female
# Access the fields by name
print(person2.name) # Output: Alice
print(person2.age) # Output: 25
print(person2.gender) # Output: female
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In this example, we defined a new named tuple class called Person that has three named fields: name, age, and gender. We then created a new instance of the Person class and assigned it to a variable called person1. Finally, we accessed the fields of the person1 instance by name using dot notation.
One of the main advantages of using namedtuple instead of a regular tuple is that the fields have names, which makes the code more readable and self-documenting. Additionally, namedtuple instances are immutable, which means that you can't modify their fields directly. This can help prevent bugs and make your code more reliable.
Another advantage of namedtuple is that it provides a few useful methods and attributes that are not available on regular tuples. For example, you can use the ._asdict() method to convert a named tuple instance to a dictionary:
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# Convert the named tuple to a dictionary
person_dict = person1._asdict()
print(person_dict)
# Output: OrderedDict([('name', 'Alice'), ('age', 25), ('gender', 'female')])
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You can also use the ._replace() method to create a new named tuple instance with one or more fields replaced:
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# Create a new named tuple instance with the name field replaced
person2 = person1._replace(name='Bob')
print(person2)
# Output: Person(name='Bob', age=25, gender='female')
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Finally, you can use the ._fields attribute to access the names of the fields in a named tuple class:
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# Print the names of the fields in the Person named tuple class
print(Person._fields) # Output: ('name', 'age', 'gender')
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namedtuple is a powerful tool in Python's collections module that allows you to create lightweight classes with named fields. By using named tuples instead of regular tuples, you can make your code more readable and self-documenting, while also taking advantage of the useful methods and attributes that named tuples provide.