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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 mip_bipartitions(mechanism, purview, node_labels=None):
 r"""Return an generator of all |small_phi| bipartitions of a mechanism over a purview. Excludes all bipartitions where one half is entirely empty, *e.g*:: A ∅ ─── ✕ ─── B ∅ is not valid, but :: A ∅ ─── ✕ ─── ∅ B is. Args: mechanism (tuple[int]):
 The mechanism to partition purview (tuple[int]):
 The purview to partition Yields: Bipartition: Where each bipartition is:: bipart[0].mechanism bipart[1].mechanism ─────────────────── ✕ ─────────────────── bipart[0].purview bipart[1].purview Example: ∅ 0 ─── ✕ ─── 2 3 <BLANKLINE> ∅ 0 ─── ✕ ─── 3 2 <BLANKLINE> ∅ 0 ─── ✕ ─── 2,3 ∅ """

    numerators = bipartition(mechanism)
    denominators = directed_bipartition(purview)

    for n, d in product(numerators, denominators):
        if (n[0] or d[0]) and (n[1] or d[1]):
            yield Bipartition(Part(n[0], d[0]), Part(n[1], d[1]),
                              node_labels=node_labels)