Making `AttrContainer` work (with tab-completion, in pycharm)

[thorwhalen]

One of the main uses of dol.sources.AttrContainer is to be able to wrap mappings (say dicts) that allow a user to use tab-completion to access values through a path of keys. For example, being able to write this:

value = a.key.path

instead of

value = a['key']['path']

With dol.sources.AttrContainer, tab-completion works in browser-based jupyter, but doesn't work in PyCharm.

Is there a magic/dunder method that I can add to make it work?

If I define attributes at class definition time, tab-completion works though.

class SettingAttrWithSetattr:
    def __init__(self, **kwargs):
        for k, v in kwargs.items():
            setattr(self, k, v)

from dol.sources import AttrContainer

def wrap_mapping_with_attr_access(**kwargs):
    return type('A', (), kwargs)()  # works


# mk_instance = AttrContainer  # (tab-completion) doesn't work (in pycharm)
mk_instance = SettingAttrWithSetattr  # (tab-completion) doesn't work (in pycharm)
# mk_instance = wrap_mapping_with_attr_access  # WORKS
# mk_instance = WithHardCodedClassAttributes  # WORKS

a = mk_instance(apple=1, banana=2)

t = a.apple

setattr(a, 'cherry', 3)
tt = a.cherry  # tab-complete DOES NOT work

a.cherry = 3 
tt = a.cherry  # tab-complete works

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