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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 store(self, server, username, secret):
 """ Store credentials for `server`. Raises a `StoreError` if an error occurs. """

        data_input = json.dumps({
            'ServerURL': server,
            'Username': username,
            'Secret': secret
        }).encode('utf-8')
        return self._execute('store', data_input)