def Z_6_func(*, C, Z_3, Z_4, Z_5, a_0, B_θ, v_φ, ρ):
    """
    Compute the value of the variable Z_6
    """
    return Z_5 + 2 * a_0 * B_θ ** 2 * v_φ * (C + Z_3) / (v_φ ** 2 * ρ + 2 *
        a_0 * Z_3 * Z_4)
