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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 iau2000a(jd_tt):
 """Compute Earth nutation based on the IAU 2000A nutation model. `jd_tt` - Terrestrial Time: Julian date float, or NumPy array of floats Returns a tuple ``(delta_psi, delta_epsilon)`` measured in tenths of a micro-arcsecond. Each value is either a float, or a NumPy array with the same dimensions as the input argument. """

    # Interval between fundamental epoch J2000.0 and given date.

    t = (jd_tt - T0) / 36525.0

    # Compute fundamental arguments from Simon et al. (1994), in radians.

    a = fundamental_arguments(t)

    # ** Luni-solar nutation **
    # Summation of luni-solar nutation series (in reverse order).

    arg = nals_t.dot(a)
    fmod(arg, tau, out=arg)

    sarg = sin(arg)
    carg = cos(arg)

    stsc = array((sarg, t * sarg, carg)).T
    ctcs = array((carg, t * carg, sarg)).T

    dpsi = tensordot(stsc, lunisolar_longitude_coefficients)
    deps = tensordot(ctcs, lunisolar_obliquity_coefficients)

    # Compute and add in planetary components.

    if getattr(t, 'shape', ()) == ():
        a = t * anomaly_coefficient + anomaly_constant
    else:
        a = (outer(anomaly_coefficient, t).T + anomaly_constant).T
    a[-1] *= t

    fmod(a, tau, out=a)
    arg = napl_t.dot(a)
    fmod(arg, tau, out=arg)
    sc = array((sin(arg), cos(arg))).T

    dpsi += tensordot(sc, nutation_coefficients_longitude)
    deps += tensordot(sc, nutation_coefficients_obliquity)

    return dpsi, deps