Access function to be pickled as attribute, not method, to avoid error.

[jhtimmins]

Currently, a static function is getting saved to DagFileProcessorAgent as an instance attribute, so it gets treated like an instance method when pickled, causing an error. By using getattr to access the attribute we can avoid this issue.

Related to issue #8674

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[ashb]

LOLwhat. Thanks pickle.

Is _processor_factory marked as @staticmethod? If not it should be, and then probably this becomes

Suggested change

	getattr(self, "_processor_factory"),
	type(self)._processor_factory,

[jhtimmins]

@ashb I agree, for purposes of consistency. But I actually think getattr is more clear. IMO type() makes it look like it's a class attribute, which isn't the case.

[jhtimmins]

Actually, that's not true. Apparently pylint expects type(self) to access an explicitly declared class attribute, whereas getattr has no such requirement. Since _processor_factory is declared at runtime, and is really a dynamic instance attribute, I think it makes sense to stay with getattr.

Also, I tried declaring _processor_factory at the class level and using type(self)._processor_factory, but it lead to an error in the child process. This didn't seem worth debugging just to use type(self).