Relevance of typename in namedtuple

Question

from collections import namedtuple

Point = namedtuple(\'whatsmypurpose\',[\'x\',\'y\'])
p = Point(11,22)
print(p)

Output:

whatsmyp         


        

Answer 1

'whatsmypurpose' gives the new subclass its type name. From the docs:

collections.namedtuple(typename, field_names, verbose=False,rename=False)
Returns a new tuple subclass named typename.

Here is an example:

>>> from collections import namedtuple
>>> Foo = namedtuple('Foo', ['a', 'b'])
>>> type(Foo)

>>> a = Foo(a = 1, b = 2)
>>> a
Foo(a=1, b=2)
>>> Foo = namedtuple('whatsmypurpose', ['a', 'b'])
>>> a = Foo(a = 1, b = 2)
>>> a
whatsmypurpose(a=1, b=2)
>>> 

---

Set the verbose parameter to True and you can see the complete whatsmypurpose class definition.

>>> Foo = namedtuple('whatsmypurpose', ['a', 'b'], verbose=True)
from builtins import property as _property, tuple as _tuple
from operator import itemgetter as _itemgetter
from collections import OrderedDict

class whatsmypurpose(tuple):
    'whatsmypurpose(a, b)'

    __slots__ = ()

    _fields = ('a', 'b')

    def __new__(_cls, a, b):
        'Create new instance of whatsmypurpose(a, b)'
        return _tuple.__new__(_cls, (a, b))

    @classmethod
    def _make(cls, iterable, new=tuple.__new__, len=len):
        'Make a new whatsmypurpose object from a sequence or iterable'
        result = new(cls, iterable)
        if len(result) != 2:
            raise TypeError('Expected 2 arguments, got %d' % len(result))
        return result

    def _replace(_self, **kwds):
        'Return a new whatsmypurpose object replacing specified fields with new values'
        result = _self._make(map(kwds.pop, ('a', 'b'), _self))
        if kwds:
            raise ValueError('Got unexpected field names: %r' % list(kwds))
        return result

    def __repr__(self):
        'Return a nicely formatted representation string'
        return self.__class__.__name__ + '(a=%r, b=%r)' % self

    def _asdict(self):
        'Return a new OrderedDict which maps field names to their values.'
        return OrderedDict(zip(self._fields, self))

    def __getnewargs__(self):
        'Return self as a plain tuple.  Used by copy and pickle.'
        return tuple(self)

    a = _property(_itemgetter(0), doc='Alias for field number 0')

    b = _property(_itemgetter(1), doc='Alias for field number 1')