keys = ['none', 'false', 'zero', 'empty', 'missed']
data = {'none':None, 'false':False, 'zero':0, 'empty':[], 'one':1}
 
def naive(k):
	return data[k] if k in data else 'missed'
 
def smart(k):
	v = data.get(k)
	return v if v is not None else 'missed'
 
def stupid(k):
	v = data.get(k)
	return v if v else 'missed'
 
unique_object = []
def verysmart(k):
	v = data.get(k,unique_object)
	return v if v is not unique_object else 'missed'
 
def test(method):
	print(method)
	for k in keys:
		print(k, method(k))
	print()
 
test(naive)
test(stupid)
test(smart)
test(verysmart)
 

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