Monkey patch functions and methods proxy.

mokeyproxy.py

from functools import wraps
from operator import attrgetter
from importlib import import_module
from collections import Counter
import re

def packages(pfqn):
    dots_n = len(pfqn.split('.'))
    for i in range(dots_n):
        yield pfqn.rsplit('.', i)[0]

def objgetter(pfqn):
    for p in packages(pfqn):
        try:
            module = import_module(p)
        except ImportError:
            pass
        else:
            object_path = re.sub(r'^{}\.'.format(p), '', pfqn)
            if '.' not in object_path:
                parent = module
            else:
                parent_path = object_path.rsplit('.', 1)[0]
                parent = attrgetter(parent_path)(module)
            obj = attrgetter(object_path)(module)
            return obj, parent
    else:
        raise ImportError('Cant find an importable at {}'.format(pfqn))

    
def proxyfunc(pfqn, target_attr):
    def decorator(func):
        obj, parent = objgetter(pfqn)
        setattr(parent, obj.__name__, func)
        setattr(func, target_attr, obj)
        return func
    return decorator

from pprint import pprint
p = 'foopkg.foomodule.FooClass.BarClass.barmethod'
q = 'foopkg.foomodule.foofunc'
pprint(objgetter(p))
pprint(objgetter(q))

@proxyfunc(q, 'target')
def foofunc():
    return foofunc.target().upper()

@proxyfunc(p, 'target')
def barmethod(self):
    return barmethod.target(self).upper()

from foopkg.foomodule import foofunc as f
print(f()) # FOO VALUE 

from foopkg.foomodule import FooClass

print(FooClass.BarClass().barmethod()) # BAR VALUE