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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 period(A,M1,M2):
 """ calculate binary period from separation. Parameters A : float separation A Rsun. M1, M2 : float M in Msun. Returns ------- p period in days. """


    A *= rsun_cm
    print(A)
    velocity = np.sqrt(grav_const*msun_g*(M1+M2)/A)
    print(old_div(velocity,1.e5))
    
    p = 2.*np.pi * A / velocity

    p  /= (60*60*24.)
    return p