patch imports during type check

6 files changed, 10 insertions, 11 deletions

diff --git a/pint/facets/context/definitions.py b/pint/facets/context/definitions.py
index a24977b..fbdb390 100644
--- a/pint/facets/context/definitions.py
+++ b/pint/facets/context/definitions.py
@@ -18,7 +18,7 @@ from ... import errors
 from ..plain import UnitDefinition
 
 if TYPE_CHECKING:
-    from pint import Quantity, UnitsContainer
+    from ..._typing import Quantity, UnitsContainer
 
 
 @dataclass(frozen=True)
diff --git a/pint/facets/group/registry.py b/pint/facets/group/registry.py
index c4ed0be..0337154 100644
--- a/pint/facets/group/registry.py
+++ b/pint/facets/group/registry.py
@@ -13,7 +13,7 @@ from typing import TYPE_CHECKING, Dict, FrozenSet
 from ... import errors
 
 if TYPE_CHECKING:
-    from pint import Unit
+    from ..._typing import Unit
 
 from ...util import build_dependent_class, create_class_with_registry
 from ..plain import PlainRegistry, UnitDefinition
diff --git a/pint/facets/plain/quantity.py b/pint/facets/plain/quantity.py
index 314cc3a..3a993f2 100644
--- a/pint/facets/plain/quantity.py
+++ b/pint/facets/plain/quantity.py
@@ -56,8 +56,7 @@ from .definitions import UnitDefinition
 
 if TYPE_CHECKING:
     from ..context import Context
-    from .unit import Unit
-    from .unit import UnitsContainer as UnitsContainerT
+    from .unit import UnitsContainer as UnitsContainerT, PlainUnit as Unit
 
     if HAS_NUMPY:
         import numpy as np  # noqa
diff --git a/pint/facets/plain/registry.py b/pint/facets/plain/registry.py
index ffa6fb4..120eaee 100644
--- a/pint/facets/plain/registry.py
+++ b/pint/facets/plain/registry.py
@@ -39,7 +39,7 @@ from typing import (
 
 if TYPE_CHECKING:
     from ..context import Context
-    from pint import Quantity, Unit
+    from ..._typing import Quantity, Unit
 
 from ..._typing import QuantityOrUnitLike, UnitLike
 from ..._vendor import appdirs
@@ -282,14 +282,14 @@ class PlainRegistry(metaclass=RegistryMeta):
 
     def __init_subclass__(cls, **kwargs):
         super().__init_subclass__()
-        cls.Unit = build_dependent_class(cls, "Unit", "_unit_class")
-        cls.Quantity = build_dependent_class(cls, "Quantity", "_quantity_class")
+        cls.Unit: Unit = build_dependent_class(cls, "Unit", "_unit_class")
+        cls.Quantity: Quantity = build_dependent_class(cls, "Quantity", "_quantity_class")
 
     def _init_dynamic_classes(self) -> None:
         """Generate subclasses on the fly and attach them to self"""
 
-        self.Unit = create_class_with_registry(self, self.Unit)
-        self.Quantity = create_class_with_registry(self, self.Quantity)
+        self.Unit: Unit = create_class_with_registry(self, self.Unit)
+        self.Quantity: Quantity = create_class_with_registry(self, self.Quantity)
 
     def _after_init(self) -> None:
         """This should be called after all __init__"""
diff --git a/pint/facets/plain/unit.py b/pint/facets/plain/unit.py
index 5fb050b..b608c05 100644
--- a/pint/facets/plain/unit.py
+++ b/pint/facets/plain/unit.py
@@ -21,7 +21,7 @@ from ...util import PrettyIPython, SharedRegistryObject, UnitsContainer
 from .definitions import UnitDefinition
 
 if TYPE_CHECKING:
-    from pint import Context
+    from ..context import Context
 
 
 class PlainUnit(PrettyIPython, SharedRegistryObject):
diff --git a/pint/facets/system/registry.py b/pint/facets/system/registry.py
index 2bab44b..d443d53 100644
--- a/pint/facets/system/registry.py
+++ b/pint/facets/system/registry.py
@@ -14,7 +14,7 @@ from typing import TYPE_CHECKING, Dict, FrozenSet, Tuple, Union
 from ... import errors
 
 if TYPE_CHECKING:
-    from pint import Quantity, Unit
+    from ..._typing import Quantity, Unit
 
 from ..._typing import UnitLike
 from ...util import UnitsContainer as UnitsContainerT