made modifications in line with Lars comments and they passed the tes…

…ts that I had previously written

bayesflow/adapters/adapter.py

@@ -76,66 +76,37 @@ def __call__(self, data: dict[str, any], *, inverse: bool = False, **kwargs) ->
         return self.forward(data, **kwargs)
 
     def __repr__(self):
-        str_transf = ''
-        for i in range(0, len(self.transforms)):
-            str_transf = str_transf + str(i) + ': ' + repr(self.transforms[i]) 
-            if i != len(self.transforms) - 1:
-                str_transf = str_transf + ' -> ' 
-        return f"Adapter([{str_transf}])"
+        str_transf = ""
+        if isinstance(self.transforms, list):
+            for i in range(0, len(self.transforms)):
+                str_transf = str_transf + str(i) + ": " + repr(self.transforms[i])
+                if i != len(self.transforms) - 1:
+                    str_transf = str_transf + " -> "
+            return f"Adapter([{str_transf}])"
+        else:
+            return f"Adapter([ 0: {repr(self.transforms)}])"
 
     def __getitem__(self, index):
-        if isinstance(index, slice):
-            if index.start > index.stop:
-                raise IndexError("Index slice must be positive integers such that a < b for adapter[a:b]")
-            if index.stop < len(self.transforms):
-                sliced_transforms = self.transforms[index]
-                new_adapter = Adapter(transforms=sliced_transforms)
-                return new_adapter
-            else:
-                raise IndexError("Index slice out of range")
-
-        elif isinstance(index, int):
-            if index < 0:
-                index = index + len(self.transforms)  # negative indexing
-            if index < 0 or index >= len(self.transforms):
-                raise IndexError("Adapter index out of range.")
-            sliced_transforms = self.transforms[index]
-            new_adapter = Adapter(transforms=sliced_transforms)
-            return new_adapter
-        else:
-            raise TypeError("Invalid index type. Must be int or slice.")
+        return Adapter(transforms=self.transforms[index])
 
     def __setitem__(self, index, new_value):
         if not isinstance(new_value, Adapter):
             raise TypeError("new_value must be an Adapter instance")
 
-        new_transform = new_value.transforms
+        # new_transform = new_value.transforms
 
-        if len(new_transform) == 0:
+        # To be tested
+        if len(new_value.transforms) == 0:
             raise ValueError(
                 "new_value is an Adapter instance without any specified transforms, new_value Adapter must contain at least one transform."
             )
 
         if isinstance(index, slice):
-            if index.start > index.stop:
-                raise IndexError("Index slice must be positive integers such that a < b for adapter[a:b]")
-
-            if index.stop < len(self.transforms):
-                self.transforms[index] = new_transform
-
-            else:
-                raise IndexError("Index slice out of range")
+            self.transforms[index] = new_value.transforms[:]
 
         elif isinstance(index, int):
-            if index < 0:  # negative indexing
-                index = index + len(self.transforms)
-
-            if index < 0 or index >= len(self.transforms):
-                raise IndexError("Index out of range.")
-                # could add that if the index is out of range, like index == len
-                # then we just add the transform
+            self.transforms[index : index + 1] = new_value.transforms[:]
 
-            self.transforms[index] = new_transform
         else:
             raise TypeError("Invalid index type. Must be int or slice.")
 
@@ -165,7 +136,7 @@ def apply(
         self.transforms.append(transform)
         return self
 
-    # Begin of transformed derived from transform classes
+    # Begin of transforms derived from transform classes
     def as_set(self, keys: str | Sequence[str]):
         if isinstance(keys, str):
             keys = [keys]