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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 set_title(self, index, title):
 """Sets the title of a container page. Parameters index : int Index of the container page title : unicode New title """

        # JSON dictionaries have string keys, so we convert index to a string
        index = unicode_type(int(index))
        self._titles[index] = title
        self.send_state('_titles')