Fix _async2sync to pass a correct self value

Initialize a _super variable in __init__ which is an instance of the async base class and is used as the self argument to async methods so that the class can await internal methods

src/replit/database/__init__.py

@@ -300,13 +300,14 @@ class AsyncReplitDb:
         Returns:
             A string representation of the database object.
         """
-        return f"<ReplitDb(db_url={self.db_url!r})>"
+        return f"<{self.__class__.__name__}(db_url={self.db_url!r})>"
 
 
 def _async2sync(coro: Callable) -> None:
     @functools.wraps(coro)
     def sync_func(self: object, *args: Any, **kwargs: Any) -> Any:
-        return asyncio.run(coro(self, *args, **kwargs))
+        res = asyncio.run(coro(self._super, *args, **kwargs))
+        return res
 
     return sync_func
 
@@ -318,6 +319,37 @@ class JSONKey(AsyncJSONKey):
     you don't have to do it manually.
     """
 
+    def __init__(
+        self,
+        db: Any,
+        key: str,
+        dtype: JSON_TYPE,
+        get_default: Callable = None,
+        discard_bad_data: bool = False,
+        do_raise: bool = False,
+    ) -> None:
+        """Initialize the key.
+
+        Args:
+            db (Any): An instance of ReplitDb
+            key (str): The key to read
+            dtype (JSON_TYPE): The datatype the key should be, can be typing.Any.
+            get_default (Callable): A function that returns the default
+                value if the key is not set. If it is None (the default) the dtype
+                argument is used.
+            discard_bad_data (bool): Don't prompt if bad data is read, overwrite it
+                with the default. Defaults to False.
+            do_raise (bool): Whether to raise exceptions when errors are encountered.
+        """
+        self._super = AsyncJSONKey(
+            db=db,
+            key=key,
+            dtype=dtype,
+            get_default=get_default,
+            discard_bad_data=discard_bad_data,
+            do_raise=do_raise,
+        )
+
     get = _async2sync(AsyncJSONKey.get)
     set = _async2sync(AsyncJSONKey.set)
 
@@ -325,6 +357,14 @@ class JSONKey(AsyncJSONKey):
 class ReplitDb(AsyncReplitDb):
     """Client interface with the Replit Database."""
 
+    def __init__(self, db_url: str) -> None:
+        """Initialize the class.
+
+        Args:
+            db_url (str): The database URL to connect to.
+        """
+        self._super = AsyncReplitDb(db_url)
+
     def __getitem__(self, item: str) -> str:
         """Retrieve a key from the database.