python namedtuple函数的使用

from collections import namedtuple
Friend = namedtuple('Friend', ['name', 'gender', 'address', 'star', 'signature'])
RidingRoad = Friend('RidingRoad', 'male', 'Mars', 'The five-star high praise',
  'Change the world by Program!\n'
  'Do what you like!\n'
  'Live what you want!')
print(RidingRoad.name)
print(RidingRoad.gender)
print(RidingRoad.address)
print(RidingRoad.star)
print(RidingRoad.signature)

RidingRoad
male
Mars
The five-star high praise
Change the world by Program!
Do what you like!
Live what you want!

for key, value in RidingRoad.__dict__.items():
 print(key, value)
print("*" * 30)
for key in RidingRoad.__dict__.keys():
 print('{}: '.format(key), eval('RidingRoad.{}'.format(key)))
print("*" * 30)
for value in RidingRoad.__dict__.values():
 print(value)

('name', 'RidingRoad')
('gender', 'male')
('address', 'Mars')
('star', 'The five-star high praise')
('signature', 'Change the world by Program!\nDo what you like!\nLive what you want!')
******************************
('name: ', 'RidingRoad')
('gender: ', 'male')
('address: ', 'Mars')
('star: ', 'The five-star high praise')
('signature: ', 'Change the world by Program!\nDo what you like!\nLive what you want!')
******************************
RidingRoad
male
Mars
The five-star high praise
Change the world by Program!
Do what you like!
Live what you want!

# Fill-in the class template
 class_definition = _class_template.format(
  typename = typename,
  field_names = tuple(field_names),
  num_fields = len(field_names),
  arg_list = repr(tuple(field_names)).replace("'", "")[1:-1],
  repr_fmt = ', '.join(_repr_template.format(name=name)
 for name in field_names),
  field_defs = '\n'.join(_field_template.format(index=index, name=name)
for index, name in enumerate(field_names))
 )
 if verbose:
  print class_definition

_class_template = '''\
class {typename}(tuple):
 '{typename}({arg_list})'
 __slots__ = ()
 _fields = {field_names!r}
 def __new__(_cls, {arg_list}):
  'Create new instance of {typename}({arg_list})'
  return _tuple.__new__(_cls, ({arg_list}))
 @classmethod
 def _make(cls, iterable, new=tuple.__new__, len=len):
  'Make a new {typename} object from a sequence or iterable'
  result = new(cls, iterable)
  if len(result) != {num_fields:d}:
raise TypeError('Expected {num_fields:d} arguments, got %d' % len(result))
  return result
 def __repr__(self):
  'Return a nicely formatted representation string'
  return '{typename}({repr_fmt})' % self
 def _asdict(self):
  'Return a new OrderedDict which maps field names to their values'
  return OrderedDict(zip(self._fields, self))
 def _replace(_self, **kwds):
  'Return a new {typename} object replacing specified fields with new values'
  result = _self._make(map(kwds.pop, {field_names!r}, _self))
  if kwds:
raise ValueError('Got unexpected field names: %r' % kwds.keys())
  return result
 def __getnewargs__(self):
  'Return self as a plain tuple.  Used by copy and pickle.'
  return tuple(self)
 __dict__ = _property(_asdict)
 def __getstate__(self):
  'Exclude the OrderedDict from pickling'
  pass
{field_defs}
'''

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