Fix map caching notebooks
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Previously, caching results with `.map()` didn't work in notebooks.
To reuse a result, `.map()` serializes the functions with `dill.dumps` and then it hashes it.

The problem is that when using `dill.dumps` to serialize a function, it also saves its origin (filename + line no.) and the origin of all the `globals` this function needs. However for notebooks and shells, the filename looks like \<ipython-input-13-9ed2afe61d25\> and the line no. changes often.

To fix the problem, I added a new dispatch function for code objects that ignore the origin of the code if it comes from a notebook or a python shell.

I tested these cases in a notebook:
- lambda functions
- named functions
- methods
- classmethods
- staticmethods
- classes that implement `__call__`

The caching now works as expected for all of them :)
I also tested the caching in the demo notebook and it works fine !
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