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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 _build(lhs, rhs):
 """Stores the wire assignment details until finalize is called."""

    _check_under_condition()
    final_predicate, pred_set = _current_select()
    _check_and_add_pred_set(lhs, pred_set)
    _predicate_map.setdefault(lhs, []).append((final_predicate, rhs))