Custom Tooltip

[engineervix]

I've been trying to customize the tooltip on a multibar chart and from my observations, it seems the tooltip text is always in the form " ... etc etc ... at horizontal_axis_value" or " ... etc etc on horizontal_axis_value" (where horizontal axis is time-based). The keywords here are the at and the on.

How can I change this in my python code to be, for example " ... etc etc ... for horizontal_axis_value"?

Thanks.