Whenever you create a primitive that can have a variable number of output terminals, create them as you go, to ensure that all possible paths of flow are apparent.
每当创建一个输出终端数量可变的原语时，可按照您的进展创建这些终端以确保流的所有可能路径是明显的。
2
Unfortunately, the way doctest parses apparent sessions treats blank lines as ending sessions — so output like the return value of pyobj_printer needs to be munged slightly to be tested.