'Set attributes that are generated automatically.'

def _auto_attrs(self):

    if (not self.T):
        self.T = [i.gen for i in self.D]
    if (not self.x):
        self.x = self.T[0]
    self.cases = [get_case(d, t) for (d, t) in zip(self.D, self.T)]
    self.level = (-1)
    self.t = self.T[self.level]
    self.d = self.D[self.level]
    self.case = self.cases[self.level]
