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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 new(self, boot_system_id):
        # type: (bytes) -> None
        '''
        A method to create a new Boot Record.

        Parameters:
         boot_system_id - The system identifier to associate with this Boot
                          Record.
        Returns:
         Nothing.
        '''
        if self._initialized:
            raise Exception('Boot Record already initialized')

        self.boot_system_identifier = boot_system_id.ljust(32, b'\x00')
        self.boot_identifier = b'\x00' * 32
        self.boot_system_use = b'\x00' * 197  # This will be set later

        self._initialized = True