diff --git a/docs/api/typing_validation.validation_failure.rst b/docs/api/typing_validation.validation_failure.rst
index 33fb694..3763a04 100644
--- a/docs/api/typing_validation.validation_failure.rst
+++ b/docs/api/typing_validation.validation_failure.rst
@@ -15,6 +15,13 @@ FailureTreeVisitor
     :show-inheritance:
     :members:
 
+InvalidNumpyDTypeValidationFailure
+----------------------------------
+
+.. autoclass:: typing_validation.validation_failure.InvalidNumpyDTypeValidationFailure
+    :show-inheritance:
+    :members:
+
 MissingKeysValidationFailure
 ----------------------------
 
diff --git a/docs/conf.py b/docs/conf.py
index 5e424ff..f656fbd 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -33,9 +33,9 @@
 # built documents.
 #
 # The full version, including alpha/beta/rc tags.
-release = "1.2.4"
+release = "1.2.9"
 # The short X.Y version.
-version = "1.2.4"
+version = "1.2.9"
 
 
 # -- General configuration ---------------------------------------------------
diff --git a/typing_validation/__init__.py b/typing_validation/__init__.py
index ea70364..0dea2f2 100644
--- a/typing_validation/__init__.py
+++ b/typing_validation/__init__.py
@@ -2,7 +2,7 @@
     Runtime validation using type hints.
 """
 
-__version__ = "1.2.4"
+__version__ = "1.2.9"
 
 from .inspector import TypeInspector, UnsupportedType
 from .validation import (
diff --git a/typing_validation/inspector.py b/typing_validation/inspector.py
index 97ab058..28c4fac 100644
--- a/typing_validation/inspector.py
+++ b/typing_validation/inspector.py
@@ -332,13 +332,13 @@ def _repr(
             name = param.__name__
             bound = param.__bound__
             if bound is None:
-                lines = [indent+f"TypeVar({name!r})"]
+                lines = [indent + f"TypeVar({name!r})"]
             else:
                 bound_lines, idx = self._repr(idx + 1, level + 1)
                 lines = [
-                    indent+f"TypeVar({name!r}, bound=",
+                    indent + f"TypeVar({name!r}, bound=",
                     *bound_lines,
-                    indent+")"
+                    indent + ")",
                 ]
             return lines, idx
         if tag == "union":
@@ -423,9 +423,11 @@ def _repr(
                 return lines, idx
             assert isinstance(param, int)
             lines = [
-                indent + f"{pending_type.__name__}["
-                if pending_type is not None
-                else indent + "Tuple["
+                (
+                    indent + f"{pending_type.__name__}["
+                    if pending_type is not None
+                    else indent + "Tuple["
+                )
             ]
             for _ in range(param):
                 item_lines, idx = self._repr(idx + 1, level + 1)
diff --git a/typing_validation/validation.py b/typing_validation/validation.py
index e8b38d3..4f597b6 100644
--- a/typing_validation/validation.py
+++ b/typing_validation/validation.py
@@ -10,7 +10,15 @@
 from keyword import iskeyword
 import sys
 import typing
-from typing import Any, ForwardRef, Hashable, Optional, TypeVar, Union, get_type_hints
+from typing import (
+    Any,
+    ForwardRef,
+    Hashable,
+    Optional,
+    TypeVar,
+    Union,
+    get_type_hints,
+)
 import typing_extensions
 
 from .validation_failure import (
@@ -220,6 +228,7 @@ def _type_error(
     setattr(error, "validation_failure", validation_failure)
     return error
 
+
 def _typevar_error(val: Any, t: Any, bound_error: TypeError) -> TypeError:
     assert hasattr(bound_error, "validation_failure"), bound_error
     cause = getattr(bound_error, "validation_failure")
@@ -229,6 +238,7 @@ def _typevar_error(val: Any, t: Any, bound_error: TypeError) -> TypeError:
     setattr(error, "validation_failure", validation_failure)
     return error
 
+
 def _idx_type_error(
     val: Any, t: Any, idx_error: TypeError, *, idx: int, ordered: bool
 ) -> TypeError:
@@ -524,6 +534,7 @@ def _extract_dtypes(t: Any) -> typing.Sequence[Any]:
             dtype for member in t.__args__ for dtype in _extract_dtypes(member)
         ]
     import numpy as np  # pylint: disable = import-outside-toplevel
+
     if hasattr(t, "__origin__"):
         t_origin = t.__origin__
         if t_origin in {
@@ -542,8 +553,10 @@ def _extract_dtypes(t: Any) -> typing.Sequence[Any]:
         return [t]
     raise TypeError()
 
+
 def _validate_numpy_array(val: Any, t: Any) -> None:
     import numpy as np  # pylint: disable = import-outside-toplevel
+
     if not isinstance(val, TypeInspector):
         _validate_type(val, np.ndarray)
     assert hasattr(t, "__args__"), _missing_args_msg(t)
@@ -588,6 +601,7 @@ def _validate_typevar(val: Any, t: TypeVar) -> None:
         except TypeError as e:
             raise _typevar_error(val, t, e) from None
 
+
 # def _validate_callable(val: Any, t: Any) -> None:
 #     """
 #         Callable validation
diff --git a/typing_validation/validation_failure.py b/typing_validation/validation_failure.py
index a4007a2..0263cac 100644
--- a/typing_validation/validation_failure.py
+++ b/typing_validation/validation_failure.py
@@ -197,9 +197,9 @@ def __repr__(self) -> str:
 
     def _str_type_descr(self, type_quals: tuple[str, ...] = ()) -> str:
         descr = (
-            "type alias" if isinstance(self.t, str)
-            else "type variable" if isinstance(self.t, TypeVar)
-            else "type"
+            "type alias"
+            if isinstance(self.t, str)
+            else "type variable" if isinstance(self.t, TypeVar) else "type"
         )
         if type_quals:
             descr = " ".join(type_quals) + " " + descr