diff --git a/development/actual_donwload.py b/development/actual_donwload.py
index ad8f1d0..be10369 100644
--- a/development/actual_donwload.py
+++ b/development/actual_donwload.py
@@ -1,15 +1,13 @@
+import logging
+
 import music_kraken
 
-import logging
 print("Setting logging-level to DEBUG")
 logging.getLogger().setLevel(logging.DEBUG)
 
 if __name__ == "__main__":
     commands = [
-        "s: #a Crystal F",
-        "10",
-        "1",
-        "3",
+        "s: #a Ghost Bath",
     ]
 
     
diff --git a/music_kraken/objects/artwork.py b/music_kraken/objects/artwork.py
index 1423c3c..40c6115 100644
--- a/music_kraken/objects/artwork.py
+++ b/music_kraken/objects/artwork.py
@@ -20,7 +20,7 @@ class ArtworkVariant:
     url: str
     width: Optional[int] = None
     height: Optional[int] = None
-    image_format: Optional[str] = ""
+    image_format: Optional[str] = None
 
     def __hash__(self) -> int:
         return custom_hash(self.url)
@@ -31,6 +31,13 @@ class ArtworkVariant:
     def __contains__(self, other: str) -> bool:
         return custom_hash(other) == hash(self.url)
 
+    def __merge__(self, other: ArtworkVariant) -> None:
+        for key, value in other.__dict__.items():
+            if value is None:
+                continue
+
+            if getattr(self, key) is None:
+                setattr(self, key, value)
 
 @dataclass
 class Artwork:
@@ -55,10 +62,9 @@ class Artwork:
         variant = self.search_variant(kwargs.get("url"))
 
         if variant is None:
-            variant, kwargs = create_dataclass_instance(ArtworkVariant, **kwargs)
+            variant, kwargs = create_dataclass_instance(ArtworkVariant, kwargs)
             self.variants.append(variant)
 
-        variant.url = url
         variant.__dict__.update(kwargs)
 
     @property
@@ -91,8 +97,6 @@ class ArtworkCollection:
         self._data = []
         self.extend(data)
 
-       
-
     def search_artwork(self, url: str) -> Optional[ArtworkVariant]:
         for artwork in self._data:
             if url in artwork:
@@ -106,18 +110,19 @@ class ArtworkCollection:
     def _create_new_artwork(self, **kwargs) -> Tuple[Artwork, dict]:
         kwargs["artwork_type"] = kwargs.get("artwork_type", self.artwork_type)
 
-        return create_dataclass_instance(ArtworkVariant, dict(**kwargs))
+        return create_dataclass_instance(Artwork, dict(**kwargs))
 
-    def add_data(self, url: str, **kwargs) -> None:
+    def add_data(self, url: str, **kwargs) -> Artwork:
         kwargs["url"] = url
 
         artwork = self.search_artwork(url)
 
         if artwork is None:
-            artwork, kwargs = self._create_new_artwork(url=url)
+            artwork, kwargs = self._create_new_artwork(**kwargs)
             self._data.append(artwork)
 
-        artwork.add_data(url, **kwargs)
+        artwork.add_data(**kwargs)
+        return artwork
 
     def append(self, value: Union[Artwork, ArtworkVariant, dict], **kwargs):
         """
@@ -144,6 +149,8 @@ class ArtworkCollection:
         """
         This will make the artworks ready for download
         """
+        from ..connection import Connection
+
         for artwork in self._data:
             for variants in artwork.variants:
                 pass
diff --git a/music_kraken/utils/__init__.py b/music_kraken/utils/__init__.py
index a0be99c..95013e5 100644
--- a/music_kraken/utils/__init__.py
+++ b/music_kraken/utils/__init__.py
@@ -156,6 +156,7 @@ def create_dataclass_instance(t, data: dict):
         Tuple[Type, dict]: The created instance and a dict, containing the data, which was not used in the creation
     """
     
-    data = {k: v for k, v in data.items() if hasattr(t, k)}
-    removed_data = {k: v for k, v in data.items() if not hasattr(t, k)}
-    return t(**data), removed_data
+    needed_data = {k: v for k, v in data.items() if k in t.__dataclass_fields__}
+    removed_data = {k: v for k, v in data.items() if k not in t.__dataclass_fields__}
+
+    return t(**needed_data), removed_data
diff --git a/music_kraken/utils/string_processing.py b/music_kraken/utils/string_processing.py
index b53d245..d001c1e 100644
--- a/music_kraken/utils/string_processing.py
+++ b/music_kraken/utils/string_processing.py
@@ -1,3 +1,4 @@
+import re
 import string
 from functools import lru_cache
 from pathlib import Path
@@ -237,5 +238,6 @@ def is_url(value: Any) -> bool:
     
     if not isinstance(value, str):
         return True
-
-    return re.match(URL_PATTERN, query) is not None
+        
+    # value has to be a string
+    return re.match(URL_PATTERN, value) is not None