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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 are_stringable_keys(self, m):
 """Test whether the keys within a map are stringable - a simple map, that can be optimized and whose keys can be cached """

        for x in m.keys():
            if len(self.handlers[x].tag(x)) != 1:
                return False
        return True