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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 delete_contexts(self, context_id_list):
 """Delete contexts from the ContextManager. Args: context_id_list (list):
 a list of context ids Returns: None """

        for c_id in context_id_list:
            if c_id in self._contexts:
                del self._contexts[c_id]