change imports to pydantic for ForwardRef to avoid crashes on 3.6

ormar/fields/foreign_key.py

@@ -1,9 +1,9 @@
 import uuid
 from dataclasses import dataclass
-from typing import Any, ForwardRef, List, Optional, TYPE_CHECKING, Tuple, Type, Union
+from typing import Any, List, Optional, TYPE_CHECKING, Tuple, Type, Union
 
 from pydantic import BaseModel, create_model
-from pydantic.typing import evaluate_forwardref
+from pydantic.typing import ForwardRef, evaluate_forwardref
 from sqlalchemy import UniqueConstraint
 
 import ormar  # noqa I101

ormar/fields/many_to_many.py

@@ -1,6 +1,6 @@
-from typing import Any, ForwardRef, List, Optional, TYPE_CHECKING, Tuple, Type, Union
+from typing import Any, List, Optional, TYPE_CHECKING, Tuple, Type, Union
 
-from pydantic.typing import evaluate_forwardref
+from pydantic.typing import ForwardRef, evaluate_forwardref
 import ormar  # noqa: I100
 from ormar.fields import BaseField
 from ormar.fields.foreign_key import ForeignKeyField

ormar/models/helpers/models.py

@@ -1,6 +1,7 @@
-from typing import Dict, ForwardRef, List, Optional, TYPE_CHECKING, Tuple, Type
+from typing import Dict, List, Optional, TYPE_CHECKING, Tuple, Type
 
-import ormar
+from pydantic.typing import ForwardRef
+import ormar  # noqa: I100
 from ormar.fields.foreign_key import ForeignKeyField
 from ormar.models.helpers.pydantic import populate_pydantic_default_values
 

tests/test_forward_refs.py

@@ -1,10 +1,9 @@
 # type: ignore
-from typing import ForwardRef, List
-
 import databases
 import pytest
 import sqlalchemy
 import sqlalchemy as sa
+from pydantic.typing import ForwardRef
 from sqlalchemy import create_engine
 
 import ormar