diff --git a/tests/fixtures/wrapper/sample.py b/tests/fixtures/wrapper/sample.py
index e9ff6726a..30faf9dc1 100644
--- a/tests/fixtures/wrapper/sample.py
+++ b/tests/fixtures/wrapper/sample.py
@@ -4,10 +4,10 @@
 
 obj = Wrapper(
     alpha='ααα',
-    bravo=[
+    bravo=iter([
         1,
         2,
-    ],
+    ]),
     charlie=[
         Charlie(
             value='δδδ',
diff --git a/xsdata/utils/collections.py b/xsdata/utils/collections.py
index 0bdc1bff6..ab1e8ec3b 100644
--- a/xsdata/utils/collections.py
+++ b/xsdata/utils/collections.py
@@ -3,6 +3,7 @@
     Any,
     Callable,
     Dict,
+    Generator,
     Iterable,
     Iterator,
     List,
@@ -20,7 +21,7 @@ def is_array(value: Any) -> bool:
     if isinstance(value, tuple):
         return not hasattr(value, "_fields")
 
-    return isinstance(value, (list, set, frozenset))
+    return isinstance(value, (list, set, frozenset, Generator))
 
 
 def unique_sequence(items: Iterable[T], key: Optional[str] = None) -> List[T]: