def reaction_weight(reaction):
    """Return the metabolite weight times its stoichiometric coefficient."""

    if len(reaction.metabolites) != 1:
        raise ValueError('Reaction weight is only defined for single '
                         'metabolite products or educts.')

    met, coeff = next(iteritems(reaction.metabolites))

    return [coeff * met.formula_weight]
def reaction_weight(reaction):
    """Return the metabolite weight times its stoichiometric coefficient."""

    if len(reaction.metabolites) != 1:
        raise ValueError('Reaction weight is only defined for single '
                         'metabolite products or educts.')

    met, coeff = next(iteritems(reaction.metabolites))

    return [coeff * met.formula_weight]
def reaction_weight ( reaction ) : if len ( reaction . metabolites ) != 1 : raise ValueError ( 'Reaction weight is only defined for single ' 'metabolite products or educts.' ) met , coeff = next ( iteritems ( reaction . metabolites ) ) return [ coeff * met . formula_weight ]
Return the metabolite weight times its stoichiometric coefficient.
Return the metabolite weight times its stoichiometric coefficient .