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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 process_multientry(entry_list, prod_comp, coeff_threshold=1e-4):
 """ Static method for finding a multientry based on a list of entries and a product composition. Essentially checks to see if a valid aqueous reaction exists between the entries and the product composition and returns a MultiEntry with weights according to the coefficients if so. Args: entry_list ([Entry]):
 list of entries from which to create a MultiEntry prod_comp (Composition):
 composition constraint for setting weights of MultiEntry coeff_threshold (float):
 threshold of stoichiometric coefficients to filter, if weights are lower than this value, the entry is not returned """

        dummy_oh = [Composition("H"), Composition("O")]
        try:
            # Get balanced reaction coeffs, ensuring all < 0 or conc thresh
            # Note that we get reduced compositions for solids and non-reduced
            # compositions for ions because ions aren't normalized due to
            # their charge state.
            entry_comps = [e.composition for e in entry_list]
            rxn = Reaction(entry_comps + dummy_oh, [prod_comp])
            coeffs = -np.array([rxn.get_coeff(comp) for comp in entry_comps])
            # Return None if reaction coeff threshold is not met
            # TODO: this filtration step might be put somewhere else
            if (coeffs > coeff_threshold).all():
                return MultiEntry(entry_list, weights=coeffs.tolist())
            else:
                return None
        except ReactionError:
            return None