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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 _delta_t_supconj_perpass(period, ecc, per0):
 """ time shift between superior conjuction and periastron passage """

    ups_sc = np.pi/2-per0
    E_sc = 2*np.arctan( np.sqrt((1-ecc)/(1+ecc)) * np.tan(ups_sc/2) )
    M_sc = E_sc - ecc*np.sin(E_sc)
    return period*(M_sc/2./np.pi)