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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 spin1y_from_xi1_phi_a_phi_s(xi1, phi_a, phi_s):
 """Returns y-component spin for primary mass. """

    phi1 = phi1_from_phi_a_phi_s(phi_s, phi_a)
    return xi1 * numpy.sin(phi1)