How to get skin vertex position?

Hello, so there’s my problem, I have a body out of vertex points and a skin modifier, now I need the skin radius (which is the same for x and y) with the location
I can loop through the skin points and add them to a list aswell as the vertex points, but how do I know that the first vertex is also the first in the skin modiefier?

 import bpy
import mathutils
from mathutils import Vector
import random

splineList = [] #list of vertex points I created

#list of skin points (where I set the radius)
for v in[0].data:
    randVar = random.uniform(0.05,0.3)
    v.radius = randVar , randVar