def METHOD_NAME(mechanism, reaction_info, candidates_for_removal):
    """Remove all reactions that generate quadratic coupling.
    Method 2 removes forward, backward or both reactions.
    """
    reactions_to_keep = []
    forward_to_remove = []
    for orig_idx, _ in reaction_info.idxmap.items():
        reaction = mechanism.reaction(orig_idx)
        if orig_idx in candidates_for_removal:
            if (
                "f" in candidates_for_removal[orig_idx]
                and "r" in candidates_for_removal[orig_idx]
            ):
                continue
            elif "f" in candidates_for_removal[orig_idx]:
                if reaction.reversible:
                    forward_to_remove.append(reaction)
                    reactions_to_keep.append(reaction)
            elif "r" in candidates_for_removal[orig_idx]:
                reaction.reversible = False
                reactions_to_keep.append(reaction)
        else:
            reactions_to_keep.append(reaction)
    return reactions_to_keep, forward_to_remove