docs: def save_method_args(method):
  	"""
  	Wrap a method such that when it is called, the args and kwargs are
  	saved on the method.
  
  	>>> class MyClass:
  	...     @save_method_args
  	...     def method(self, a, b):
  	...         print(a, b)
  	>>> my_ob = MyClass()
  	>>> my_ob.method(1, 2)
  	1 2
  	>>> my_ob._saved_method.args
  	(1, 2)
  	>>> my_ob._saved_method.kwargs
  	{}
  	>>> my_ob.method(a=3, b='foo')
  	3 foo
  	>>> my_ob._saved_method.args
  	()
  	>>> my_ob._saved_method.kwargs == dict(a=3, b='foo')
  	True
  
  	The arguments are stored on the instance, allowing for
  	different instance to save different args.
  
  	>>> your_ob = MyClass()
  	>>> your_ob.method({str('x'): 3}, b=[4])
  	{'x': 3} [4]
  	>>> your_ob._saved_method.args
  	({'x': 3},)
  	>>> my_ob._saved_method.args
  	()
  	"""
  	args_and_kwargs = collections.namedtuple('args_and_kwargs', 'args kwargs')
  
  	@functools.wraps(method)
  	def wrapper(self, *args, **kwargs):
  		attr_name = '_saved_' + method.__name__
  		attr = args_and_kwargs(args, kwargs)
  		setattr(self, attr_name, attr)
  		return method(self, *args, **kwargs)
  	return wrapper