Is possible to edit the legend size of a WMS layer?

Is possible to change the size of the legend image of a WMS layer? Changing the legend width like in the script below doesn't have effect on the vizualization. I would like to resize the "image" of the legend. My script is:

map = vis.As[MapChart]() #vis is the parameter equal to the map chart visualization

for layer in map.Layers:    
    if layer.Title == "myWmsLayer":