Accessing matplotlib colorbar title in SHAP Dependence Plot

Question

I want to change the title of the colorbar in the SHAP dependence plot. A dependence plot is created with:

shap.dependence_plot("Age", shap_values, X, interaction_index="Education-Num", show=False)

The plot can be extracted with

fig, ax = plt.gcf(), plt.gca()

This allows for changes e.g. to the x-limits.

plt.xlim(0,10)

When trying to access the colorbar title with

clb = plt.colorbar()
clb.ax.set_title('New Label',fontsize=8)

a secondary colorbar is created, in addition to the existing one. How can the existing colorbar title be overwritten, without creating a new one? Thank you in advance.