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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(self, fragment_info):
 """ Get the value associated with the given key. :param fragment_info: the text key :type fragment_info: tuple of str ``(language, text)`` :raises: KeyError if the key is not present in the cache """

        if not self.is_cached(fragment_info):
            raise KeyError(u"Attempt to get text not cached")
        return self.cache[fragment_info]