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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def once(func):
 	""" 	Decorate func so it's only ever called the first time. 	This decorator can ensure that an expensive or non-idempotent function 	will not be expensive on subsequent calls and is idempotent. 	6 	6 	6 	To reset the stored value, simply clear the property ``saved_result``. 	12 	12 	Or invoke 'reset()' on it. 	0 	0 	"""

	@functools.wraps(func)
	def wrapper(*args, **kwargs):
		if not hasattr(wrapper, 'saved_result'):
			wrapper.saved_result = func(*args, **kwargs)
		return wrapper.saved_result
	wrapper.reset = lambda: vars(wrapper).__delitem__('saved_result')
	return wrapper