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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 busday_count_mask_NaT(begindates, enddates, out=None):
 """ Simple of numpy.busday_count that returns `float` arrays rather than int arrays, and handles `NaT`s by returning `NaN`s where the inputs were `NaT`. Doesn't support custom weekdays or calendars, but probably should in the future. See Also -------- np.busday_count """

    if out is None:
        out = empty(broadcast(begindates, enddates).shape, dtype=float)

    beginmask = isnat(begindates)
    endmask = isnat(enddates)

    out = busday_count(
        # Temporarily fill in non-NaT values.
        where(beginmask, _notNaT, begindates),
        where(endmask, _notNaT, enddates),
        out=out,
    )

    # Fill in entries where either comparison was NaT with nan in the output.
    out[beginmask | endmask] = nan
    return out