diff --git a/src/zeep/transports.py b/src/zeep/transports.py
index d2136373..99e28bb8 100644
--- a/src/zeep/transports.py
+++ b/src/zeep/transports.py
@@ -18,6 +18,7 @@
 
 try:
     from packaging.version import Version
+
     if httpx is None or Version(httpx.__version__) < Version("0.26.0"):
         HTTPX_PROXY_KWARG_NAME = "proxies"
     else:
diff --git a/src/zeep/wsdl/__init__.py b/src/zeep/wsdl/__init__.py
index 55351fa2..a12d735c 100644
--- a/src/zeep/wsdl/__init__.py
+++ b/src/zeep/wsdl/__init__.py
@@ -1,15 +1,15 @@
 """
-    zeep.wsdl
-    ---------
+zeep.wsdl
+---------
 
-    The wsdl module is responsible for parsing the WSDL document. This includes
-    the bindings and messages.
+The wsdl module is responsible for parsing the WSDL document. This includes
+the bindings and messages.
 
-    The structure and naming of the modules and classses closely follows the
-    WSDL 1.1 specification.
+The structure and naming of the modules and classses closely follows the
+WSDL 1.1 specification.
 
-    The serialization and deserialization of the SOAP/HTTP messages is done
-    by the zeep.wsdl.messages modules.
+The serialization and deserialization of the SOAP/HTTP messages is done
+by the zeep.wsdl.messages modules.
 
 
 """
diff --git a/src/zeep/wsdl/definitions.py b/src/zeep/wsdl/definitions.py
index 66fe3b9c..47b9d2e7 100644
--- a/src/zeep/wsdl/definitions.py
+++ b/src/zeep/wsdl/definitions.py
@@ -1,18 +1,18 @@
 """
-    zeep.wsdl.definitions
-    ~~~~~~~~~~~~~~~~~~~~~
+zeep.wsdl.definitions
+~~~~~~~~~~~~~~~~~~~~~
 
-    A WSDL document exists out of a number of definitions. There are 6 major
-    definitions, these are:
+A WSDL document exists out of a number of definitions. There are 6 major
+definitions, these are:
 
-     - types
-     - message
-     - portType
-     - binding
-     - port
-     - service
+ - types
+ - message
+ - portType
+ - binding
+ - port
+ - service
 
-    This module defines the definitions which occur within a WSDL document,
+This module defines the definitions which occur within a WSDL document,
 
 """
 
diff --git a/src/zeep/wsdl/messages/__init__.py b/src/zeep/wsdl/messages/__init__.py
index d1287dc3..0272eb73 100644
--- a/src/zeep/wsdl/messages/__init__.py
+++ b/src/zeep/wsdl/messages/__init__.py
@@ -1,18 +1,18 @@
 """
-    zeep.wsdl.messages
-    ~~~~~~~~~~~~~~~~~~
+zeep.wsdl.messages
+~~~~~~~~~~~~~~~~~~
 
-    The messages are responsible for serializing and deserializing
+The messages are responsible for serializing and deserializing
 
-    .. inheritance-diagram::
-            zeep.wsdl.messages.soap.DocumentMessage
-            zeep.wsdl.messages.soap.RpcMessage
-            zeep.wsdl.messages.http.UrlEncoded
-            zeep.wsdl.messages.http.UrlReplacement
-            zeep.wsdl.messages.mime.MimeContent
-            zeep.wsdl.messages.mime.MimeXML
-            zeep.wsdl.messages.mime.MimeMultipart
-       :parts: 1
+.. inheritance-diagram::
+        zeep.wsdl.messages.soap.DocumentMessage
+        zeep.wsdl.messages.soap.RpcMessage
+        zeep.wsdl.messages.http.UrlEncoded
+        zeep.wsdl.messages.http.UrlReplacement
+        zeep.wsdl.messages.mime.MimeContent
+        zeep.wsdl.messages.mime.MimeXML
+        zeep.wsdl.messages.mime.MimeMultipart
+   :parts: 1
 
 """
 
diff --git a/src/zeep/wsdl/messages/base.py b/src/zeep/wsdl/messages/base.py
index 1493577d..1fe5a3f9 100644
--- a/src/zeep/wsdl/messages/base.py
+++ b/src/zeep/wsdl/messages/base.py
@@ -1,6 +1,6 @@
 """
-    zeep.wsdl.messages.base
-    ~~~~~~~~~~~~~~~~~~~~~~~
+zeep.wsdl.messages.base
+~~~~~~~~~~~~~~~~~~~~~~~
 
 """
 
diff --git a/src/zeep/wsdl/messages/http.py b/src/zeep/wsdl/messages/http.py
index 39fae02d..f2bc7cf1 100644
--- a/src/zeep/wsdl/messages/http.py
+++ b/src/zeep/wsdl/messages/http.py
@@ -1,6 +1,6 @@
 """
-    zeep.wsdl.messages.http
-    ~~~~~~~~~~~~~~~~~~~~~~~
+zeep.wsdl.messages.http
+~~~~~~~~~~~~~~~~~~~~~~~
 
 """
 
diff --git a/src/zeep/wsdl/messages/mime.py b/src/zeep/wsdl/messages/mime.py
index f15ebadf..0973dfa1 100644
--- a/src/zeep/wsdl/messages/mime.py
+++ b/src/zeep/wsdl/messages/mime.py
@@ -1,6 +1,6 @@
 """
-    zeep.wsdl.messages.mime
-    ~~~~~~~~~~~~~~~~~~~~~~~
+zeep.wsdl.messages.mime
+~~~~~~~~~~~~~~~~~~~~~~~
 
 """
 
diff --git a/src/zeep/wsdl/messages/soap.py b/src/zeep/wsdl/messages/soap.py
index 808325ab..cedbe3f0 100644
--- a/src/zeep/wsdl/messages/soap.py
+++ b/src/zeep/wsdl/messages/soap.py
@@ -1,6 +1,6 @@
 """
-    zeep.wsdl.messages.soap
-    ~~~~~~~~~~~~~~~~~~~~~~~
+zeep.wsdl.messages.soap
+~~~~~~~~~~~~~~~~~~~~~~~
 
 """
 
diff --git a/src/zeep/wsdl/parse.py b/src/zeep/wsdl/parse.py
index 51ce4333..91064796 100644
--- a/src/zeep/wsdl/parse.py
+++ b/src/zeep/wsdl/parse.py
@@ -1,6 +1,6 @@
 """
-    zeep.wsdl.parse
-    ~~~~~~~~~~~~~~~
+zeep.wsdl.parse
+~~~~~~~~~~~~~~~
 
 """
 
diff --git a/src/zeep/wsdl/utils.py b/src/zeep/wsdl/utils.py
index bbc28145..63965b14 100644
--- a/src/zeep/wsdl/utils.py
+++ b/src/zeep/wsdl/utils.py
@@ -1,6 +1,6 @@
 """
-    zeep.wsdl.utils
-    ~~~~~~~~~~~~~~~
+zeep.wsdl.utils
+~~~~~~~~~~~~~~~
 
 """
 
diff --git a/src/zeep/wsdl/wsdl.py b/src/zeep/wsdl/wsdl.py
index 80807d6b..ff279d3d 100644
--- a/src/zeep/wsdl/wsdl.py
+++ b/src/zeep/wsdl/wsdl.py
@@ -1,6 +1,6 @@
 """
-    zeep.wsdl.wsdl
-    ~~~~~~~~~~~~~~
+zeep.wsdl.wsdl
+~~~~~~~~~~~~~~
 
 """
 
diff --git a/src/zeep/xsd/__init__.py b/src/zeep/xsd/__init__.py
index f2501046..bf3ea5bf 100644
--- a/src/zeep/xsd/__init__.py
+++ b/src/zeep/xsd/__init__.py
@@ -1,6 +1,6 @@
 """
-    zeep.xsd
-    --------
+zeep.xsd
+--------
 
 """
 
diff --git a/tests/test_xsd_builtins.py b/tests/test_xsd_builtins.py
index 4063771e..a20c095f 100644
--- a/tests/test_xsd_builtins.py
+++ b/tests/test_xsd_builtins.py
@@ -371,11 +371,11 @@ def test_pythonvalue(self):
 class TestHexBinary:
     def test_xmlvalue(self):
         instance = builtins.HexBinary()
-        assert instance.xmlvalue(b"\xFF") == b"\xFF"
+        assert instance.xmlvalue(b"\xff") == b"\xff"
 
     def test_pythonvalue(self):
         instance = builtins.HexBinary()
-        assert instance.pythonvalue(b"\xFF") == b"\xFF"
+        assert instance.pythonvalue(b"\xff") == b"\xff"
 
 
 class TestBase64Binary: