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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 add_context(self, name, indices, level=None):
 """ Add a new context level to the hierarchy. By default, new contexts are added to the lowest level of the hierarchy. To insert the context elsewhere in the hierarchy, use the ``level`` argument. For example, ``level=0`` would insert the context at the highest level of the hierarchy. Parameters name : str indices : list Token indices at which each chunk in the context begins. level : int Level in the hierarchy at which to insert the context. By default, inserts context at the lowest level of the hierarchy """


        self._validate_context((name, indices))

        if level is None:
            level = len(self.contexts_ranked)
        self.contexts_ranked.insert(level, name)
        self.contexts[name] = indices