code: def get_f(reciever, sender):
      diff = sender[1:3] - reciever[1:3]
      distance = norm(diff)
      if distance < 1:
          distance = 1
      return G * reciever[0] * sender[0] / (distance**3) * diff
  
file_path: dgl/examples/pytorch/graphsim/n_body_sim.py
imports: from __future__ import absolute_import, division, print_function
  import argparse
  import os
  from math import cos, pi, radians, sin
  import numpy
label_desc: Use image node_id 3 for calling a global function with example usage: get_f(reciever, sender) and returns: unknown