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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 is_hidden_container(self, key, val):
 """ The key is not one of the Mapfile keywords, and its values are a list """


        if key in ("layers", "classes", "styles", "symbols", "labels",
                   "outputformats", "features", "scaletokens",
                   "composites") and isinstance(val, list):
            return True
        else:
            return False