value = obj.attribute
value = getattr(obj, "attribute")

#一个模块支持html、text、xml等格式的打印，根据传入的formate参数的不同，调用不同的函数实现几种格式的输出import statsout def output(data, format="text"):                           output_function = getattr(statsout, "output_%s" %format) return output_function(data)

class storage(dict):# __call__方法用于实例自身的调用#达到()调用的效果def __call__ (self, key):try:return self[key]except KeyError, k:return Nones = storage()
s['key'] = 'value'
print s(key) #调用__call__

class A(object):  def __init__(self):  self.name = 'from __dicts__: zdy'  def __getattr__(self, item):  if item == 'name':  return 'from __getattr__: zdy'  elif item == 'age':  return 26  a = A()
print a.name # 从__dict__里获得的
print a.age # 从__getattr__获得的  

class A(object):def __setattr__(self, *args, **kwargs):  print 'call func set attr'  return object.__setattr__(self, *args, **kwargs) 

class A(object):def __delattr__(self, *args, **kwargs):  print 'call func del attr'  return object.__delattr__(self, *args, **kwargs)  

class _Executable(object):def __init__(self, client, method, path):self._client = clientself._method = methodself._path = path#__call__函数实现_Executable函数对象为可调用的def __call__(self, **kw):method = _METHOD_MAP[self._method]if method==_HTTP_POST and 'pic' in kw:method = _HTTP_UPLOADreturn _http_call('%s%s.json' % (self._client.api_url, self._path), method, self._client.access_token, **kw)def __str__(self):return '_Executable (%s %s)' % (self._method, self._path)__repr__ = __str__class _Callable(object):def __init__(self, client, name):self._client = clientself._name = namedef __getattr__(self, attr):if attr=='get':　　　　　　　#初始化_Executable对象，调用__init__函数return _Executable(self._client, 'GET', self._name)if attr=='post':return _Executable(self._client, 'POST', self._name)name = '%s/%s' % (self._name, attr)return _Callable(self._client, name)def __str__(self):return '_Callable (%s)' % self._name__repr__ = __str__

class APIClient(object):'''API client using synchronized invocation.'''... def __getattr__(self, attr):if '__' in attr:return getattr(self.get, attr)return _Callable(self, attr)

client = APIClient(...)
#会调用__getattr__函数，从而调用__call__函数
client.something.get()