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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 all(self, sort=None, **kwargs):
 """ Returns a list of media from this library section. Parameters: sort (string):
 The sort string """

        sortStr = ''
        if sort is not None:
            sortStr = '?sort=' + sort
        
        key = '/library/sections/%s/all%s' % (self.key, sortStr)
        return self.fetchItems(key, **kwargs)