diff --git a/.gitignore b/.gitignore
index fddc013..37688fa 100644
--- a/.gitignore
+++ b/.gitignore
@@ -104,3 +104,6 @@ venv.bak/
 
 # mypy
 .mypy_cache/
+
+# JetBrains
+.idea/
diff --git a/django_inlinecss/templatetags/inlinecss.py b/django_inlinecss/templatetags/inlinecss.py
index c778ddf..82b9728 100644
--- a/django_inlinecss/templatetags/inlinecss.py
+++ b/django_inlinecss/templatetags/inlinecss.py
@@ -4,7 +4,7 @@
 from __future__ import unicode_literals
 
 from django import template
-from django.utils.encoding import smart_text
+from django.utils.encoding import smart_str
 
 from django_inlinecss import conf
 
@@ -23,7 +23,7 @@ def render(self, context):
         for expression in self.filter_expressions:
             path = expression.resolve(context, True)
             if path is not None:
-                path = smart_text(path)
+                path = smart_str(path)
 
             css_loader = conf.get_css_loader()()
             css = ''.join((css, css_loader.load(path)))
diff --git a/setup.py b/setup.py
index c1ff0c5..87dfc00 100644
--- a/setup.py
+++ b/setup.py
@@ -21,7 +21,7 @@
 URL = 'https://github.com/roverdotcom/django-inlinecss'
 EMAIL = 'philip@rover.com'
 AUTHOR = 'Philip Kimmey'
-REQUIRES_PYTHON = '>=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*, <3.7'
+REQUIRES_PYTHON = '>=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*, <3.11'
 VERSION = None
 
 # What packages are required for this module to be executed?
@@ -140,6 +140,10 @@ def run(self):
         'Programming Language :: Python :: 3.4',
         'Programming Language :: Python :: 3.5',
         'Programming Language :: Python :: 3.6',
+        'Programming Language :: Python :: 3.7',
+        'Programming Language :: Python :: 3.8',
+        'Programming Language :: Python :: 3.9',
+        'Programming Language :: Python :: 3.10',
         'Topic :: Communications :: Email',
         'Topic :: Text Processing :: Markup :: HTML',
     ],