Set the edge layer in pyvis

Question

I would like to have thick edges (black in the image below) on top of thin edges (grey in the image below) in pyvis, is this somehow possible?

import networkx as nx
import numpy as np
from pyvis.network import Network

def rgb_to_hex(r, g, b):
    return '#{:02x}{:02x}{:02x}'.format(r, g, b)

G = nx.complete_graph(20)
net = Network()
net.from_nx(G)

for edge in net.edges:
    random_number = np.random.rand()*0.6 + 0.2
    edge["color"] = rgb_to_hex(int(255 * (1 - random_number)), int(255 * (1 - random_number)), int(255 * (1 - random_number)))
    edge["width"] = int(4 * random_number)

net.toggle_physics(False)
net.save_graph("test.html")