How to draw a box plot with white face color on top of a violin plot and swarm plot

Question

I want to draw the following box-plot with white face color overlaid on a violin plot and swarmplot, something similar to the following plot:

This is the following code that I was trying:

ax = sns.violinplot(x="variable", 
                    y="value",
                    data=pd.melt(box_plot_df),
                    inner=None,
                    width=0.9,
                    edgecolor="black",
                    scale="width",
                    palette="Set1")

border_colors = ["red", "blue"]

# Set transparancy for all violins
for i in range(len(ax.collections)):
    ax.collections[i].set_alpha(0.4)
    ax.collections[i].set_edgecolor(border_colors[i])
    
ax = sns.boxplot(x="variable", 
                 y="value", 
                 width= 0.3,
                 medianprops={"color": "black", "linewidth" :2, "linestyle" : "--"},
                 boxprops={'facecolor': 'white'},
                 data=pd.melt(box_plot_df),              
                )
  
for patch in ax.patches:
    r, g, b, a = patch.get_facecolor()
    patch.set_facecolor((1.0, 1.0, 1.0, 1.0))


ax = sns.swarmplot(x="variable", 
                   y="value",
                   hue=None, 
                   data=pd.melt(box_plot_df), 
                   palette="Set1", 
                   size=5, 
                   marker="o")

I was getting the following output:

I was struggling to get the absolutely white face-color for each box. I am not sure, why I am not getting an absolute white color.