pymen · January 13, 2022 15:06 · Jan 13, 2022
diff --git a/LazyObject b/LazyObject
@@ -0,0 +1,64 @@
+        import operator
+
+        class LazyObject:
+
+            _wrapped = None
+            _is_init = False
+
+            def __init__(self, factory, **factory_kwargs):
+                # Assign using __dict__ to avoid the setattr method.
+                self.__dict__['_factory'] = factory
+                self.__dict__['_kwargs'] = factory_kwargs
+
+            def _setup(self):
+                self._wrapped = self._factory(**self._kwargs)
+                self._is_init = True
+
+            def new_method_proxy(func):
+                """
+                Util function to help us route functions
+                to the nested object.
+                """
+
+                def inner(self, *args):
+                    if not self._is_init:
+                        self._setup()
+                    return func(self._wrapped, *args)
+
+                return inner
+
+            def __setattr__(self, name, value):
+                # These are special names that are on the LazyObject.
+                # every other attribute should be on the wrapped object.
+                if name in {"_is_init", "_wrapped"}:
+                    self.__dict__[name] = value
+                else:
+                    if not self._is_init:
+                        self._setup()
+                    setattr(self._wrapped, name, value)
+
+            def __delattr__(self, name):
+                if name == "_wrapped":
+                    raise TypeError("can't delete _wrapped.")
+                if not self._is_init:
+                    self._setup()
+                delattr(self._wrapped, name)
+
+            __getattr__ = new_method_proxy(getattr)
+            __bytes__ = new_method_proxy(bytes)
+            __str__ = new_method_proxy(str)
+            __bool__ = new_method_proxy(bool)
+            __dir__ = new_method_proxy(dir)
+            __hash__ = new_method_proxy(hash)
+            __class__ = property(new_method_proxy(operator.attrgetter("__class__")))
+            __eq__ = new_method_proxy(operator.eq)
+            __lt__ = new_method_proxy(operator.lt)
+            __gt__ = new_method_proxy(operator.gt)
+            __ne__ = new_method_proxy(operator.ne)
+            __hash__ = new_method_proxy(hash)
+            __getitem__ = new_method_proxy(operator.getitem)
+            __setitem__ = new_method_proxy(operator.setitem)
+            __delitem__ = new_method_proxy(operator.delitem)
+            __iter__ = new_method_proxy(iter)
+            __len__ = new_method_proxy(len)
+            __contains__ = new_method_proxy(operator.contains)