'The (generic) base class takes a cb_value_dictionary of
question-answer pairs. Questions are specified by the respective
SASL callback id\'s. The mech argument is a string that specifies
the SASL mechaninsm to be uesd.'

def __init__(self, cb_value_dict, mech):

    self.cb_value_dict = (cb_value_dict or {})
    self.mech = mech
