def customer1(balance):
    if balance > 0:
        if balance >= 1000:
            return 'reliable'
        else:
            return 'precarious'
    else:
        if balance > -1000:
            return 'short on'
        else:
            return 'defaulting'

def customer2(balance):
    if balance >= 1000:
        return 'reliable'
    elif balance > 0:
        return 'precarious'
    elif balance > -1000:
        return 'short on'
    else:
        return 'defaulting'

# choose the function
#customer = customer1
customer = customer2