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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 advance(self, length):
 """Advance the cursor in data buffer 'length' bytes."""

        new_position = self._position + length
        if new_position < 0 or new_position > len(self._data):
            raise Exception('Invalid advance amount (%s) for cursor.  '
                            'Position=%s' % (length, new_position))
        self._position = new_position