def getUser(self, email):
        for u in users:
            if email == users[u].get('email'):
                return users[u]
        return None
walking a tree bottom-up based on dictionary
dataset/ETHPy150Open pneff/wsgiservice/examples/user.py/UserEmailView.getUser--crossover with--dataset/ETHPy150Open statsmodels/statsmodels/statsmodels/sandbox/regression/runmnl.py/RU2NMNL.calc_prob