Conditional Format A Row Based On Changing Values In One Column

Is it possible to format a row of cells (B7:KX7) depending on the value in column (G7:G1000) changing?

For example column G might have the following value entered into them.

A
A
A
B
B
B
C
C
C

So all the rows containing the letter A would be formatted one colour, then it would notice it changed to B and format all the rows with the letter B in, then C etc... The letters would always appear in blocks of 10 or more (representing students in a group) so it wouldn't go A,B,A,B,C,D,E

I am not bothered about the letter being tied to a certain colour, it just needs to change when the letter changes. I'd have no more than 10 different variables in this column, meaning no more than 10 different colours to format. Formatting would be black text with different coloured backgrounds.