Returns a new tuple subclass named typename

namedtuple is immutable

from collections import namedtuple

Point = namedtuple('Point', ['x', 'y']) # define a type and its fields

p = Point(x=11, y=22)
#p = Point(11, 22)

# access
x, y = p # unpack like a regular tuple
print(x, y)

print(p[0], p[1]) # Access by index
print(p.x, p.y) # Access by keyname
print(getattr(p, 'x'), getattr(p, 'y')) # Access Using getattr

print('x is {}, y is {}'.format(*p))
			

# _make, makes a new instance from an existing sequence or iterable
from collections import namedtuple

Point = namedtuple('Point', ['x', 'y']) # define a type and its fields

l = [11, 22]
p = Point._make(l)
            

# _asdict, return a dict which maps field names to their corresponding values
from collections import namedtuple

Point = namedtuple('Point', ['x', 'y']) # define a type and its fields

p = Point(x=11, y=22)

d = p._asdict() # dict
            

# **, convert a dictionary into the namedtuple
from collections import namedtuple

Point = namedtuple('Point', ['x', 'y']) # define a type and its fields

d = {'x':11, 'y':22}
p = Point(**d)
            

# _fields, get all the keynames of a namedtuplefrom collections import namedtuple
from collections import namedtuple

Point = namedtuple('Point', ['x', 'y']) # define a type and its fields
p = Point(x=11, y=22)

print(p._fields) # ('x', 'y')
            

# _replace, return a new instance of the named tuple replacing specified fields with new values
from collections import namedtuple

Point = namedtuple('Point', ['x', 'y']) # define a type and its fields
p = Point(x=11, y=22)

p2 = p._replace(x=33)

print(p2)
            

# __new__, returns a new instance with assigned values to keys
from collections import namedtuple

Point = namedtuple('Point', ['x', 'y']) # define a type and its fields
p = Point(x=11, y=22)

p2 = p.__new__(Point, 10, 20)
            

# __getnewargs__, returns the namedtuple as a plain tuple
from collections import namedtuple

Point = namedtuple('Point', ['x', 'y']) # define a type and its fields
p = Point(x=11, y=22)

t = p.__getnewargs__() # tuple, (11, 22)
            

from collections import namedtuple

class Point(namedtuple('Point', ['x', 'y'])):

    @property
    def hypot(self):
        return (self.x ** 2 + self.y ** 2) ** 0.5

    def __str__(self):
        return 'Point: x=%6.3f  y=%6.3f  hypot=%6.3f' % (self.x, self.y, self.hypot)

p = Point(1, 2)
# p = Point._make([1, 2])
print(p)
            

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