diff --git a/src/pyrad3/dictionary.py b/src/pyrad3/dictionary.py
index 1878de3..cd1b2bb 100644
--- a/src/pyrad3/dictionary.py
+++ b/src/pyrad3/dictionary.py
@@ -9,7 +9,17 @@ Classes and Types to parse and represent a RADIUS dictionary.
 from enum import IntEnum, Enum, auto
 from dataclasses import dataclass
 from os.path import dirname, isabs, join, normpath
-from typing import cast, Dict, Generator, IO, List, Optional, Sequence, Tuple, Union
+from typing import (
+    cast,
+    Dict,
+    Generator,
+    IO,
+    List,
+    Optional,
+    Sequence,
+    Tuple,
+    Union,
+)
 
 import logging
 
@@ -389,7 +399,10 @@ class Dictionary:
         has_tag, encrypt = self._parse_attribute_flags(tokens, line_num)
         name, attr_code, datatype = tokens[1:4]
 
-        if datatype in {"concat", "extended", "evs", "long-extended" } and self.cur_vendor != self.rfc_vendor:
+        if (
+            datatype in {"concat", "extended", "evs", "long-extended"}
+            and self.cur_vendor != self.rfc_vendor
+        ):
             raise ParseError(
                 filename,
                 'vendor attributes are not allowed to have the datatype "concat"',
@@ -440,7 +453,9 @@ class Dictionary:
             len(codes) > 1,
         )
 
-        attrcode: Union[int, Tuple[int, ...]] = codes[0] if len(codes) == 1 else tuple(codes)
+        attrcode: Union[int, Tuple[int, ...]] = codes[0] if len(
+            codes
+        ) == 1 else tuple(codes)
         self.cur_vendor.attrs[attrcode] = attribute
 
         if self.cur_vendor != self.rfc_vendor:
@@ -461,14 +476,14 @@ class Dictionary:
 
         (attr_name, key, vvalue) = tokens[1:]
         try:
-            if '.' in vvalue:
+            if "." in vvalue:
                 # quick and dirty way to make floats values an error
                 raise ValueError
             value = _parse_number(vvalue)
         except ValueError:
-            raise ParseError(filename,
-            f"Invalid number {vvalue} for VALUE {key}",
-            line_num)
+            raise ParseError(
+                filename, f"Invalid number {vvalue} for VALUE {key}", line_num
+            )
 
         attribute = self.attrindex[attr_name]
         try:
diff --git a/tests/test_dictionary.py b/tests/test_dictionary.py
index fa6107f..ebcf2dd 100644
--- a/tests/test_dictionary.py
+++ b/tests/test_dictionary.py
@@ -86,8 +86,7 @@ def test_valid_attribute_numbers(number):
 
 
 @pytest.mark.parametrize(
-    "invalid_number",
-    ["ABCD", "-1", "inf", "INF", "-INF", "2e4", "2.5e3"],
+    "invalid_number", ["ABCD", "-1", "inf", "INF", "-INF", "2e4", "2.5e3"],
 )
 def test_invalid_attribute_numbers(invalid_number):
     dictionary = StringIO(f"ATTRIBUTE NAME {invalid_number} integer64")
@@ -269,7 +268,8 @@ def test_invalid_datatypes_in_vendor_space(datatype):
 )
 def test_invalid_attribute_numbers(invalid_number):
     dictionary = StringIO(
-            f"ATTRIBUTE TEST-ATTRIBUTE 1 integer\n"
-            f"VALUE TEST-ATTRIBUTE TEST-VALUE {invalid_number}")
+        f"ATTRIBUTE TEST-ATTRIBUTE 1 integer\n"
+        f"VALUE TEST-ATTRIBUTE TEST-VALUE {invalid_number}"
+    )
     with pytest.raises(ParseError):
         Dictionary("", dictionary)