ValueError: rotation must be 'vertical', 'horizontal' or a number, not 90

[wilfred11]

When using mealy 0.2.5 with matplotlib 3.9.0, I get an error

File "C:\Users\wilfr\PycharmProjects\rai3-mealy\venv\Lib\site-packages\mealy\error_visualizer.py", line 47, in _add_new_plot
plt.xticks(x_ticks, rotation="90")

Using 90 instead of "90" makes things work.