Try compatibility with Python 3.7

great_ai/views/operators.py

@@ -1,4 +1,6 @@
-from typing import List, Literal
+from typing import List
+
+from typing_extensions import Literal  # <= Python 3.7
 
 Operator = Literal[">=", "<=", "<", ">", "!=", "=", "contains"]
 

great_ai/views/outputs/sequence_labeling_output.py

@@ -1,4 +1,6 @@
-from typing import Any, List, Literal, Optional
+from typing import Any, List, Optional
+
+from typing_extensions import Literal  # <= Python 3.7
 
 from ..hashable_base_model import HashableBaseModel
 

great_ai/views/sort_by.py

@@ -1,6 +1,5 @@
-from typing import Literal
-
 from pydantic import BaseModel
+from typing_extensions import Literal  # <= Python 3.7
 
 
 class SortBy(BaseModel):