diff --git a/djxml/xmlmodels/base.py b/djxml/xmlmodels/base.py
index 0ac3946..17cdf04 100644
--- a/djxml/xmlmodels/base.py
+++ b/djxml/xmlmodels/base.py
@@ -9,8 +9,7 @@
 from django.core.exceptions import (ObjectDoesNotExist, FieldError,
                                     MultipleObjectsReturned,)
 from django.db.models.base import subclass_exception
-from django.utils.encoding import force_text
-from django.utils.encoding import smart_bytes, smart_str
+from django.utils.encoding import smart_str
 
 from .signals import xmlclass_prepared
 from .options import Options, DEFAULT_NAMES
diff --git a/djxml/xmlmodels/fields.py b/djxml/xmlmodels/fields.py
index e96a174..d9c1e22 100644
--- a/djxml/xmlmodels/fields.py
+++ b/djxml/xmlmodels/fields.py
@@ -4,11 +4,7 @@
 from lxml import etree, isoschematron
 
 from django.core.exceptions import ValidationError
-try:
-    from django.utils.encoding import force_text as force_unicode
-except ImportError:
-    from django.utils.encoding import force_unicode
-
+from django.utils.encoding import force_str
 from .descriptors import ImmutableFieldBase, XPathFieldBase, XsltFieldBase
 from .exceptions import XmlSchemaValidationError
 from .utils import parse_datetime
@@ -105,7 +101,7 @@ def get_default(self):
         if self.has_default():
             if callable(self.default):
                 return self.default()
-            return force_unicode(self.default, strings_only=True)
+            return force_str(self.default, strings_only=True)
         return None
 
 
@@ -297,7 +293,7 @@ class XPathTextField(XPathSingleNodeField):
     def __init__(self, *args, **kwargs):
         none_vals = kwargs.pop('none_vals', None)
         if none_vals is not None:
-            self.none_vals = [force_unicode(v) for v in none_vals]
+            self.none_vals = [force_str(v) for v in none_vals]
         super(XPathTextField, self).__init__(*args, **kwargs)
 
     def validate(self, value, model_instance):
@@ -316,9 +312,9 @@ def to_python(self, value):
         if value is None:
             return value
         if isinstance(value, etree._Element):
-            return force_unicode(value.text)
+            return force_str(value.text)
         else:
-            return force_unicode(value)
+            return force_str(value)
 
 
 class XPathIntegerField(XPathTextField):
@@ -410,7 +406,7 @@ def to_python(self, value):
         if value is None:
             return value
         else:
-            return [force_unicode(getattr(v, "text", v)) for v in value]
+            return [force_str(getattr(v, "text", v)) for v in value]
 
 
 class XPathIntegerListField(XPathTextListField):
diff --git a/djxml/xmlmodels/signals.py b/djxml/xmlmodels/signals.py
index c8fe0c5..94e4a67 100644
--- a/djxml/xmlmodels/signals.py
+++ b/djxml/xmlmodels/signals.py
@@ -1,4 +1,5 @@
 from __future__ import absolute_import
 from django.dispatch import Signal
 
-xmlclass_prepared = Signal(providing_args=["class"])
+# Arguments: "class"
+xmlclass_prepared = Signal()
diff --git a/setup.py b/setup.py
index 4cf3682..be9ecc6 100644
--- a/setup.py
+++ b/setup.py
@@ -33,11 +33,14 @@
         'Programming Language :: Python',
         'Programming Language :: Python :: 3.7',
         'Programming Language :: Python :: 3.8',
+        'Programming Language :: Python :: 3.9',
+        'Programming Language :: Python :: 3.10',
         'Framework :: Django',
         'Framework :: Django :: 2.2',
         'Framework :: Django :: 3.0',
         'Framework :: Django :: 3.1',
         'Framework :: Django :: 3.2',
+        'Framework :: Django :: 4.0',
     ],
     include_package_data=True,
     zip_safe=False,
diff --git a/tox.ini b/tox.ini
index 126a8cf..0e46dc5 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,6 +1,7 @@
 [tox]
 envlist =
     py{37,38}-django{22,30,31,32}
+    py{38,39,310}-django{40}
 
 [testenv]
 commands =
@@ -10,6 +11,7 @@ deps =
     django30: Django>=3.0.13,<3.1
     django31: Django>=3.1.7,<3.2
     django32: Django>=3.2rc1,<4.0
+    django40: Django>=4.0,<4.1
 
 [testenv:pep8]
 description = Run PEP8 pycodestyle (flake8) against the djxml/ package directory
@@ -36,3 +38,5 @@ commands =
 python =
     3.7: py37
     3.8: py38
+    3.9: py39
+    3.10: py310