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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 _null_ac_sia(transition, direction, alpha=0.0):
 """Return an |AcSystemIrreducibilityAnalysis| with zero |big_alpha| and empty accounts. """

    return AcSystemIrreducibilityAnalysis(
        transition=transition,
        direction=direction,
        alpha=alpha,
        account=(),
        partitioned_account=()
    )