create text label in python using scaled centering (relative to the plot size)

plot_label.py

def ShowSolutions(n, id):
    nqReduced = 4
    nqM = 100
    for i in range(n):
        plotname = pathPrefix+foldername + 'plot-id'+str(i+1)+'.pdf'
        fig, ax = plt.subplots()
        plt.xlabel('q')
        plt.ylabel(f'λi')
        ax.text(0.15, 0.75, f'$\lambda_{i+1}$ | N={n}', horizontalalignment='center',
                verticalalignment='center', transform=ax.transAxes)
        # ax.text(0.15, 0.85, f'N=n', horizontalalignment='center',
        #         verticalalignment='center', transform=ax.transAxes)
        qValues_Red = GenerateQs(0, 3, 0.1)
        qValues_M = GenerateQs(0, 3, 0.05)
        xs_Red = LambdaEvolution(n, i+1, 0, 0.1)
        xs_M = LambdaEvolution(n, i+1, 0, 0.05)
        if(i+1 == id):
            print(f'Solution {id} for N={n}')
            print(f'Reduced | N={nqReduced}')
            print(qValues_Red)
            print(xs_Red)
            print(f'Accurate| N={nqM}')
            print(qValues_M)
            print(xs_M)
            f = open(filename, "w")
            f.write(str(qValues_M))
            f.write('\n')
            f.write(str(xs_M))
            f.close()
        ax.plot(qValues_Red, xs_Red, 'r-o', label=f'nd={nqReduced}')
        ax.plot(qValues_M, xs_M, 'b-', label=f'nd={nqM}')
        ax.legend(loc='best')
        plt.savefig(plotname, bbox_inches='tight')
        plt.close()


ShowSolutions(10, 1)