text: import numpy as np
  from numpy.testing import assert_allclose
  
  from astropy import units as u
  
  from poliastro.bodies import Earth
  
  from poliastro.twobody.rv import rv2coe
  from poliastro.twobody.classical import coe2rv, coe2mee
  from poliastro.twobody.equinoctial import mee2coe
  
  
  def test_convert_between_coe_and_rv_is_transitive():
      k = Earth.k.to(u.km**3 / u.s**2).value  # u.km**3 / u.s**2
      p = 11067.790  # u.km
      ecc = 0.83285  # u.one
      inc = np.deg2rad(87.87)  # u.rad
      raan = np.deg2rad(227.89)  # u.rad
      argp = np.deg2rad(53.38)  # u.rad
      nu = np.deg2rad(92.335)  # u.rad
  
      expected_res = (p, ecc, inc, raan, argp, nu)
  
      res = rv2coe(k, *coe2rv(k, *expected_res))
  
      assert_allclose(res, expected_res)
  
  
  def test_convert_between_coe_and_mee_is_transitive():
      p = 11067.790  # u.km
      ecc = 0.83285  # u.one
      inc = np.deg2rad(87.87)  # u.rad
      raan = np.deg2rad(227.89)  # u.rad
      argp = np.deg2rad(53.38)  # u.rad
      nu = np.deg2rad(92.335)  # u.rad
  
      expected_res = (p, ecc, inc, raan, argp, nu)
  
      res = mee2coe(*coe2mee(*expected_res))
  
      assert_allclose(res, expected_res)
  