First you need to have a yield Metric
for each color with a different name (like by adding the name of the color)
yield Metric(
f"remaining_{ink}",
remain,
levels=(20,5),
boundaries=(0,100)
)
Then in your graph definition, the metrics have to match these names exactly
graph_info["hp_officejet_remaining_combined"] = {
"metrics": [
("remaining_Yellow", "line"),
("remaining_Magenta", "line"),
("remaining_Cyan", "line"),
("remaining_Black", "line"),
],
}