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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 nltides_gw_phase_diff_isco(f_low, f0, amplitude, n, m1, m2):
 """Calculate the gravitational-wave phase shift bwtween f_low and f_isco due to non-linear tides. Parameters f_low: float Frequency from which to compute phase. If the other arguments are passed as numpy arrays then the value of f_low is duplicated for all elements in the array f0: float or numpy.array Frequency that NL effects switch on amplitude: float or numpy.array Amplitude of effect n: float or numpy.array Growth dependence of effect m1: float or numpy.array Mass of component 1 m2: float or numpy.array Mass of component 2 Returns ------- delta_phi: float or numpy.array Phase in radians """

    f0, amplitude, n, m1, m2, input_is_array = ensurearray(
        f0, amplitude, n, m1, m2)

    f_low = numpy.zeros(m1.shape) + f_low

    phi_l = nltides_gw_phase_difference(
                f_low, f0, amplitude, n, m1, m2)

    f_isco = f_schwarzchild_isco(m1+m2)

    phi_i = nltides_gw_phase_difference(
                f_isco, f0, amplitude, n, m1, m2)

    return formatreturn(phi_i - phi_l, input_is_array)