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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def spin_in_roche(s, etheta, elongan, eincl):
 """ Transform the spin s of a star on Kerpler orbit with etheta - true anomaly elongan - longitude of ascending node eincl - inclination from in the plane of sky reference frame into the Roche reference frame. """

  #  m = Rz(long).Rx(-incl).Rz(theta).Rz(pi)
  m = euler_trans_matrix(etheta, elongan, eincl)

  return np.dot(m.T, s)