How to pickle function from imported module with dill - pickle

Question

I'm trying to pickle functions with dill. I want to include the whole function and not just a reference to it. Here are my two files:
fun.py:
import dill
from foo import ppp
def qqq(me):
return me + 1
print(dill.dumps(ppp, protocol=4, recurse=True, byref=True))
print(dill.dumps(qqq, protocol=4, recurse=True, byref=True))
And foo.py
def qqq(me):
return me + 1
When I run fun.py I get the following output:
b'\x80\x04\x95\x0f\x00\x00\x00\x00\x00\x00\x00\x8c\x03foo\x94\x8c\x03ppp\x94\x93\x94.'
b'\x80\x04\x95\x90\x00\x00\x00\x00\x00\x00\x00\x8c\ndill._dill\x94\x8c\x10_create_function\x94\x93\x94(h\x00\x8c\n_load_type\x94\x93\x94\x8c\x08CodeType\x94\x85\x94R\x94(K\x01K\x00K\x01K\x02KCC\x08|\x00d\x01\x17\x00S\x00\x94NK\x01\x86\x94)\x8c\x02me\x94\x85\x94\x8c\x06fun.py\x94\x8c\x03qqq\x94K\x04C\x02\x00\x01\x94))t\x94R\x94}\x94h\rNN}\x94Nt\x94R\x94.'
I want to be able to make the first line of output be more similar to the second line, and actually encapsulate the function without the need for a context when reloaded later. Is there a way to do this?
Thanks so much!
James

Answer 1

If the module (foo) is installed on both computers, then there should be no need to do anything but import the function. So, I'll assume the question is in regard to a module that is only installed on the first machine.
It also depends on whether the module foo is "installed" on sys.path or is just available in the current directory. See:
https://github.com/uqfoundation/dill/issues/123
If it's only available in the current directory, either use dill to pickle the file itself or use something like dill.source.getsource to extract the source of the module as a string, and then transfer the string as a "pickle" (this is what ppft does).
Generally, however, dill pickles imported functions by reference, and thus assumes they are available on both sides of the load/dump.