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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 _unpack_string(self, data):
 """ Unpacks the next string from the given data :param data: A datagram, starting at a string size :return: A (string, unread_data) tuple """

        # Get the size of the string
        result, data = self._unpack("<H", data)
        size = result[0]

        # Read it
        string_bytes = data[:size]

        # Convert it
        return to_unicode(string_bytes), data[size:]