import os
import sys
from pathlib import Path


class LayeredObject:
    def __init__(self, *objects):
        self._objects = objects

    def __getattr__(self, item):
        for o in self.__dict__['_objects']:
            try:
                if isinstance(o, dict):
                    return o[item]
                elif isinstance(o, os._Environ):
                    return o[item.upper()]
                else:
                    return getattr(o, item)
            except (AttributeError, KeyError):
                pass
        raise AttributeError(f"None of the objects contained in '{self.__class__.__name__}' have attribute '{item}'.\n"
                             f"Objects contained: {[repr(o) for o in self.__dict__['_objects']]}")


def import_module(path):
    path = Path(path)
    assert path.suffix == '.py', f'expected a path to a python module, got {path}'
    sys.path.insert(1, str(path.parent))
    mod = __import__(path.stem)
    sys.path.remove(str(path.parent))
    return mod