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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 get_locale_hints():
 """ Get a list of locale hints, guessed according to Python's default locale info. """

        #/
        lang, encoding = locale.getdefaultlocale()
        ## can both be None
        
        #/
        if lang and '_' in lang:
            lang3, _, lang2 = lang.partition('_')
        else:
            lang3 = None
            lang2 = None
        
        #/
        ll_s = [encoding, lang, lang2, lang3]
        ## Encoding comes before lang intentionally, e.g.
        ##  lang |en_US| with encoding |cp936|, |cp936| takes priority.
        
        #/
        ll_s_unique = []
        
        for ll in ll_s:
            if ll:
                ll = ll.lower()
                
                if ll not in ll_s_unique:
                    ll_s_unique.append(ll)
        
        #/
        return ll_s_unique