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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 _choicerank(n_items, data, params):
 """Inner loop of ChoiceRank algorithm."""

    weights = exp_transform(params)
    adj, adj_t, traffic_in, traffic_out = data
    # First phase of message passing.
    zs = adj.dot(weights)
    # Second phase of message passing.
    with np.errstate(invalid="ignore"):
        denoms = adj_t.dot(traffic_out / zs)
    return traffic_in, denoms