Una funcion que calcule la constante Coulumb dandole vectores en x , y, z

import numpy as np
def Coulomb(q1, q2, r1=[0,0,0], r2=[0,0,0]):
    k=9e9
    r= np.sqrt((r2[0]-r1[0])**2+(r2[1]-r1[1])**2+(r2[2]-r1[2])**2)
    return k*q1*q2/r