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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 literals():
        '''Returns a list of literals
        in the Synset
        read-only
        '''
        def fget(self):
            if self.variants:
                return map(lambda x: x.literal,
                           self.variants)
            else:
                return None
 
        return locals()