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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 update(self, title, key):
 """Update this key. :param str title: (required), title of the key :param str key: (required), text of the key file :returns: bool """

        json = None
        if title and key:
            data = {'title': title, 'key': key}
            json = self._json(self._patch(self._api, data=dumps(data)), 200)
        if json:
            self._update_(json)
            return True
        return False