Could not set the Domain Gridline Stroke for chart

Hi All,

In the chart component, I am trying to change the DomainGridlineStroke​ as the default is dotted stroke and less in width.
I create a stroke and could not implement as its throwing error as following

11:34:11.403 [AWT-EventQueue-0] ERROR com.inductiveautomation.ignition.client.util.gui.ErrorUtil - Parse error for extension function “configureChart”
SyntaxError: (“no viable alternative at character ‘?’”, (’’, 27, 29, ‘\tplot.setDomainGridlineStroke?(b)\n’))

def configureChart(self, chart):
	Provides an opportunity to perform further chart configuration via
	scripting. Doesn't return anything.

		self: A reference to the component that is invoking this function.
		chart: A JFreeChart object. Refer to the JFreeChart documentation for
		       API details.
	# Put your code here
	from java.awt import Color
	from java.awt import BasicStroke
	from org.jfree.chart import renderer
	from  org.jfree.chart.renderer.xy import XYStepRenderer
	from org.jfree.chart.renderer.xy import StandardXYItemRenderer
	from org.jfree.chart.plot import XYPlot
	from org.jfree.chart import plot
	plot = chart.getPlot()
	renderer = plot.getRenderer()
	print renderer
	print str(type(renderer))+"this was"
	b = BasicStroke()
	print type(b)

What would be the issue?

A unicode parenthesis instead of an ASCII parenthesis, perhaps? Try deleting and retyping that spot.

Thanks But both the Unicode and ASCII parenthesis look the same, Moreover, I have used the same parenthesis for setRangeGridlinePaint,setRangeGridlinesVisible I did not have an issue.