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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 get_title(self, index):
 """Gets the title of a container pages. Parameters index : int Index of the container page """

        # JSON dictionaries have string keys, so we convert index to a string
        index = unicode_type(int(index))
        if index in self._titles:
            return self._titles[index]
        else:
            return None