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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 MergeWaveSets(waveset1, waveset2):
 """Return the union of the two wavelength sets. The union is computed using `numpy.union1d`, unless one or both of them is `None`. The merged result may sometimes contain numbers which are nearly equal but differ at levels as small as 1E-14. Having values this close together can cause problems due to effectively duplicate wavelength values. Therefore, wavelength values having differences smaller than or equal to ``pysynphot.spectrum.MERGETHRESH`` (defaults to 1E-12) are considered as the same. Parameters waveset1, waveset2 : array_like or `None` Wavelength sets to combine. Returns ------- MergedWaveSet : array_like or `None` Merged wavelength set. It is `None` if both inputs are such. """

    if waveset1 is None and waveset2 is not None:
        MergedWaveSet = waveset2
    elif waveset2 is None and waveset1 is not None:
        MergedWaveSet = waveset1
    elif waveset1 is None and waveset2 is None:
        MergedWaveSet = None
    else:
        MergedWaveSet = N.union1d(waveset1, waveset2)

        # The merged wave sets may sometimes contain numbers which are nearly
        # equal but differ at levels as small as 1e-14. Having values this
        # close together can cause problems down the line so here we test
        # whether any such small differences are present, with a small
        # difference defined as less than MERGETHRESH.
        #
        # If small differences are present we make a copy of the union'ed array
        # with the lower of the close together pairs removed.
        delta = MergedWaveSet[1:] - MergedWaveSet[:-1]

        if not (delta > MERGETHRESH).all():
            newlen = len(delta[delta > MERGETHRESH]) + 1
            newmerged = N.zeros(newlen, dtype=MergedWaveSet.dtype)
            newmerged[:-1] = MergedWaveSet[:-1][delta > MERGETHRESH]
            newmerged[-1] = MergedWaveSet[-1]

            MergedWaveSet = newmerged

    return MergedWaveSet