Change sparkline color on Graphical Table

from Spotfire.Dxp.Application. Visuals import VisualTypeIdentifiers
from Spotfire.Dxp.Application. Visuals.Miniatures import GraphicalTable, SparklineMiniatureVisualization 
from System.Drawing import Color 

#graphPlot is a GraphicalTable visualization script parameter
#color is a string document property holding values like "red", "blue" or "papayawhip" 

for column in graphPlot.As[GraphicalTable]() .Columns: 
    if column.Visualization.TypeId == VisualTypeIdentifiers. SparklineMiniatureVisualization: 
print column.Title
if column.Title == "Trend": 
#column.Visualization.LineColor = Color.FromArgb(R,G,B)
column.Visualization.LineColor = Color.FromName(color)

Thanks to Mike Akister and Adam W!