from operator import methodcaller

class Job(object):
  def __init__(self, jobid, inst, func):
    self.id = jobid
    self.inst = inst
    self.func = str(func)

  def __str__(self):
    return "<Object Job, id:%s, instance:%s>" % (self.id, self.inst)

class Pipeline(object):
  def __init__(self):
    self._jobs = []

  def add_jobs(self, job):
    self._jobs.append(job)

def run(self):
    for job in self._jobs:
      methodcaller(job.func)(job.inst)

使用方法：多个函数顺序执行时，可以使代码简洁，更加面对对象。

class A(object):
  def a(object):
    time.sleep(3)
    print("aa")

class B(object):
  def b(object):
    time.sleep(2)
    print("bb")

class C(object):
  def c(object):
    time.sleep(1)
    print("cc")

a = A()
b = B()
c = C()
pipe = Pipeline()

step1 = Job(1, a, "a")
step2 = Job(2, b, "b")
step3 = Job(3, c, "c")
pipe.add_jobs(step1)
pipe.add_jobs(stpe2)
pipe.add_jobs(step3)
pipe.run()