This function is used to set the contents of one or more fields to a given value. You can optionally choose to set only if the destination is empty and/or only if the source is not empty.
The supplied string may contain any of the escape sequences described in Escape Sequences.
in order to facilitate setting the rating, use a value of 0-5 which will be converted as required. If you want to write a specific value in the range of 1-255 for the internal representation of the rating, enter it as a negative number.