code: def rv_model(ts, K, e, omega, chi, P):
      
  
      assert ts.ndim == 1, 'ts must be one-dimensional'
  
      return kp.rv_model(ts, K, e, omega, chi, P)
docs: Returns the radial velocity measurements associated with the
      planets in parameters ps at times ts.  The returned array has
      shape (Nts,).