Plotly heatmap mark specific cells?

I’m using plotly heatmap and I would like to manipulate some cells to have another marker except the color specified by the chosen color pallet.
e.g. from the code:

            trace = go.Heatmap(
                x = X_labels,
                y = Y_labels,
                z = matrix,
                type = 'heatmap',
                colorscale = 'Viridis'
            data = [trace]
            fig = go.Figure(data = data)

I would like to somehow create the following image (assuming I’m passing the indices vector [(0,0),(1,3),(2,1)]