fix: better handling of text responses (#118)

## changes

small fix to handle text responses

src/data_hub/_api.py

@@ -183,15 +183,21 @@ def dynamic_function(
             )
 
         if not isinstance(response, dict):
-            response = response.json()
+            if "json" in response.headers["content-type"]:
+                response = response.json()
+            elif "text" in response.headers["content-type"]:
+                response = response.text()
+            else:
+                raise DeepOriginException(
+                    f"Uncertain response type: {response.headers}"
+                )
 
-        if "data" in response.keys():
+        if isinstance(response, dict) and "data" in response.keys():
             response = response["data"]
-            if isinstance(response, list):
-                response = [Box(item) for item in response]
-            else:
-                response = Box(response)
-        else:
+
+        if isinstance(response, list):
+            response = [Box(item) for item in response]
+        elif isinstance(response, dict):
             response = Box(response)
 
         if _stash: