add encoding

tests/test_queries/test_utils.py

@@ -0,0 +1,14 @@
+import json
+
+from ormar.queryset.utils import to_str
+
+
+def test_to_str():
+    expected_str = "[]"
+    val = json.dumps([])
+    assert expected_str == to_str(val)
+
+    expected_bytes = expected_str.encode()
+    assert isinstance(expected_bytes, bytes)
+
+    assert isinstance(to_str(expected_bytes), str)