def reverse_mapping(mapping):
	"""
	For every key, value pair, return the mapping for the
	equivalent value, key pair

	>>> reverse_mapping({'a': 'b'}) == {'b': 'a'}
	True
	"""
	keys, values = zip(*mapping.items())
	return dict(zip(values, keys))
def reverse_mapping(mapping):
	
	keys, values = zip(*mapping.items())
	return dict(zip(values, keys))
def reverse_mapping ( mapping ) : keys , values = zip ( * mapping . items ( ) ) return dict ( zip ( values , keys ) )
For every key, value pair, return the mapping for the
	equivalent value, key pair

	>>> reverse_mapping({'a': 'b'}) == {'b': 'a'}
	True
For every key value pair return the mapping for the equivalent value key pair