code: func (c *cursor) Last() bool {
  	// Ensure transaction state is valid.
  	if err := c.bucket.tx.checkClosed(); err != nil {
  		return false
  	}
  
  	// Seek to the last key in both the database and pending iterators and
  	// choose the iterator that is both valid and has the larger key.
  	c.dbIter.Last()
  	c.pendingIter.Last()
  	return c.chooseIterator(false)
  }
docs: // Last positions the cursor at the last key/value pair and returns whether or
  // not the pair exists.
  //
  // This function is part of the database.Cursor interface implementation.