diff --git a/.isort.cfg b/.isort.cfg
index e7ddf30..1d02ebd 100644
--- a/.isort.cfg
+++ b/.isort.cfg
@@ -4,8 +4,7 @@ line_length = 120
 lines_after_imports = 2
 multi_line_output = 5
 
-sections = FUTURE,STDLIB,SIX,THIRDPARTY,DJANGO,FIRSTPARTY,LOCALFOLDER
-known_six = six
+sections = FUTURE,STDLIB,THIRDPARTY,DJANGO,FIRSTPARTY,LOCALFOLDER
 known_third_party = freezegun
 known_django = django
 known_first_party = django_otp
diff --git a/Pipfile.lock b/Pipfile.lock
index 5d58dda..574e6e6 100644
--- a/Pipfile.lock
+++ b/Pipfile.lock
@@ -330,13 +330,6 @@
             ],
             "version": "==0.9.1"
         },
-        "six": {
-            "hashes": [
-                "sha256:1f1b7d42e254082a9db6279deae68afb421ceba6158efa6131de7b3003ee93fd",
-                "sha256:30f610279e8b2578cab6db20741130331735c781b56053c59c4076da27f06b66"
-            ],
-            "version": "==1.13.0"
-        },
         "snowballstemmer": {
             "hashes": [
                 "sha256:209f257d7533fdb3cb73bdbd24f436239ca3b2fa67d56f6ff88e86be08cc5ef0",
diff --git a/docs/source/conf.py b/docs/source/conf.py
index 5f0ec45..c664275 100644
--- a/docs/source/conf.py
+++ b/docs/source/conf.py
@@ -1,5 +1,3 @@
-# -*- coding: utf-8 -*-
-#
 # django-otp documentation build configuration file, created by
 # sphinx-quickstart on Fri Jul 13 09:48:33 2012.
 #
@@ -81,8 +79,8 @@
 master_doc = 'index'
 
 # General information about the project.
-project = u'django-otp'
-copyright = u'2012, Peter Sagerson'
+project = 'django-otp'
+copyright = '2012, Peter Sagerson'
 
 # The version info for the project you're documenting, acts as replacement for
 # |version| and |release|, also used in various other places throughout the
@@ -225,7 +223,7 @@
 # Grouping the document tree into LaTeX files. List of tuples
 # (source start file, target name, title, author, documentclass [howto/manual]).
 latex_documents = [
-    ('index', 'django-otp.tex', u'django-otp Documentation',
+    ('index', 'django-otp.tex', 'django-otp Documentation',
      'Peter Sagerson', 'manual'),
 ]
 
@@ -255,7 +253,7 @@
 # One entry per manual page. List of tuples
 # (source start file, name, description, authors, manual section).
 man_pages = [
-    ('index', 'django-otp', u'django-otp Documentation',
+    ('index', 'django-otp', 'django-otp Documentation',
      ['Peter Sagerson'], 1)
 ]
 
@@ -269,7 +267,7 @@
 # (source start file, target name, title, author,
 #  dir menu entry, description, category)
 texinfo_documents = [
-    ('index', 'django-otp', u'django-otp Documentation',
+    ('index', 'django-otp', 'django-otp Documentation',
      'Peter Sagerson', 'django-otp', 'One line description of project.',
      'Miscellaneous'),
 ]
diff --git a/docs/source/extend.rst b/docs/source/extend.rst
index a6c750f..cf8f8e0 100644
--- a/docs/source/extend.rst
+++ b/docs/source/extend.rst
@@ -31,7 +31,7 @@ interesting. Here's a simple implementation of a generic TOTP device::
         key = models.CharField(max_length=80,
                                validators=[hex_validator()],
                                default=lambda: random_hex(20),
-                               help_text=u'A hex-encoded secret key of up to 40 bytes.')
+                               help_text='A hex-encoded secret key of up to 40 bytes.')
 
         @property
         def bin_key(self):
diff --git a/setup.cfg b/setup.cfg
index 9212391..6129493 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -7,6 +7,3 @@ ignore =
        W504
        # line too long
        E501
-
-[bdist_wheel]
-universal = 1
diff --git a/setup.py b/setup.py
index cfa7136..52276ff 100755
--- a/setup.py
+++ b/setup.py
@@ -54,8 +54,8 @@ def find_package_data(*args, **kwargs):
         "Framework :: Django",
         "Intended Audience :: Developers",
         "License :: OSI Approved :: BSD License",
-        "Programming Language :: Python :: 2",
         "Programming Language :: Python :: 3",
+        "Programming Language :: Python :: 3 :: Only",
         "Topic :: Security",
         "Topic :: Software Development :: Libraries :: Python Modules",
     ],
@@ -72,7 +72,6 @@ def find_package_data(*args, **kwargs):
 
     install_requires=[
         'django >= 1.11',
-        'six >= 1.10.0'
     ],
     extras_require={
         'qrcode': ['qrcode'],
diff --git a/src/django_otp/admin.py b/src/django_otp/admin.py
index aa63c35..c815175 100644
--- a/src/django_otp/admin.py
+++ b/src/django_otp/admin.py
@@ -1,5 +1,3 @@
-from __future__ import absolute_import, division, print_function, unicode_literals
-
 import django
 from django import forms
 from django.contrib.admin.forms import AdminAuthenticationForm
@@ -35,17 +33,8 @@ class OTPAdminAuthenticationForm(AdminAuthenticationForm, OTPAuthenticationFormM
     # the otp_challenge submit button.
     otp_challenge = forms.CharField(required=False)
 
-    def __init__(self, *args, **kwargs):
-        super(OTPAdminAuthenticationForm, self).__init__(*args, **kwargs)
-
-        # A litle extra cheese to make it prettier.
-        minor_django_version = django.VERSION[:2]
-
-        if minor_django_version < (1, 6):
-            self.fields['otp_token'].widget.attrs['style'] = 'width: 14em;'
-
     def clean(self):
-        self.cleaned_data = super(OTPAdminAuthenticationForm, self).clean()
+        self.cleaned_data = super().clean()
         self.clean_otp(self.get_user())
 
         return self.cleaned_data
@@ -72,11 +61,11 @@ class OTPAdminSite(AdminSite):
     login_template = _admin_template_for_django_version()
 
     def __init__(self, name='otpadmin'):
-        super(OTPAdminSite, self).__init__(name)
+        super().__init__(name)
 
     def has_permission(self, request):
         """
         In addition to the default requirements, this only allows access to
         users who have been verified by a registered OTP device.
         """
-        return super(OTPAdminSite, self).has_permission(request) and request.user.is_verified()
+        return super().has_permission(request) and request.user.is_verified()
diff --git a/src/django_otp/conf.py b/src/django_otp/conf.py
index 40c5518..62a7db1 100644
--- a/src/django_otp/conf.py
+++ b/src/django_otp/conf.py
@@ -1,11 +1,7 @@
-from __future__ import absolute_import, division, print_function, unicode_literals
-
-from six import iteritems
-
 import django.conf
 
 
-class Settings(object):
+class Settings:
     """
     This is a simple class to take the place of the global settings object. An
     instance will contain all of our settings as attributes, with default values
@@ -20,7 +16,7 @@ def __init__(self):
         Loads our settings from django.conf.settings, applying defaults for any
         that are omitted.
         """
-        for name, default in iteritems(self.defaults):
+        for name, default in self.defaults.items():
             value = getattr(django.conf.settings, name, default)
             setattr(self, name, value)
 
diff --git a/src/django_otp/decorators.py b/src/django_otp/decorators.py
index f3f5f1d..1eb35bd 100644
--- a/src/django_otp/decorators.py
+++ b/src/django_otp/decorators.py
@@ -1,5 +1,3 @@
-from __future__ import absolute_import, division, print_function, unicode_literals
-
 from django.contrib.auth.decorators import user_passes_test
 
 from django_otp import user_has_device
diff --git a/src/django_otp/forms.py b/src/django_otp/forms.py
index 581d4d3..37ae451 100644
--- a/src/django_otp/forms.py
+++ b/src/django_otp/forms.py
@@ -1,15 +1,13 @@
-from __future__ import absolute_import, division, print_function, unicode_literals
-
 from django import forms
 from django.contrib.auth.forms import AuthenticationForm
-from django.utils.translation import ugettext_lazy as _
-from django.utils.translation import ungettext_lazy
+from django.utils.translation import gettext_lazy as _
+from django.utils.translation import ngettext_lazy
 
 from . import devices_for_user, match_token
 from .models import Device, VerifyNotAllowed
 
 
-class OTPAuthenticationFormMixin(object):
+class OTPAuthenticationFormMixin:
     """
     Shared functionality for
     :class:`~django.contrib.auth.forms.AuthenticationForm` subclasses that wish
@@ -62,7 +60,7 @@ class CustomAuthForm(OTPAuthenticationFormMixin, AuthenticationForm):
         'not_interactive': _('The selected OTP device is not interactive'),
         'challenge_message': _('OTP Challenge: {0}'),
         'invalid_token': _('Invalid token. Please make sure you have entered it correctly.'),
-        'n_failed_attempts': ungettext_lazy(
+        'n_failed_attempts': ngettext_lazy(
             "Verification temporarily disabled because of %(failure_count)d failed attempt, please try again soon.",
             "Verification temporarily disabled because of %(failure_count)d failed attempts, please try again soon.",
             "failure_count"),
@@ -235,7 +233,7 @@ class OTPAuthenticationForm(OTPAuthenticationFormMixin, AuthenticationForm):
     otp_challenge = forms.CharField(required=False)
 
     def clean(self):
-        self.cleaned_data = super(OTPAuthenticationForm, self).clean()
+        self.cleaned_data = super().clean()
         self.clean_otp(self.get_user())
 
         return self.cleaned_data
@@ -282,13 +280,13 @@ def verify(request):
     otp_challenge = forms.CharField(required=False)
 
     def __init__(self, user, request=None, *args, **kwargs):
-        super(OTPTokenForm, self).__init__(*args, **kwargs)
+        super().__init__(*args, **kwargs)
 
         self.user = user
         self.fields['otp_device'].choices = self.device_choices(user)
 
     def clean(self):
-        super(OTPTokenForm, self).clean()
+        super().clean()
 
         self.clean_otp(self.user)
 
diff --git a/src/django_otp/middleware.py b/src/django_otp/middleware.py
index 5d36d7b..a047099 100644
--- a/src/django_otp/middleware.py
+++ b/src/django_otp/middleware.py
@@ -1,5 +1,3 @@
-from __future__ import absolute_import, division, print_function, unicode_literals
-
 import functools
 
 from django.utils.functional import SimpleLazyObject
@@ -12,7 +10,7 @@ def is_verified(user):
     return user.otp_device is not None
 
 
-class OTPMiddleware(object):
+class OTPMiddleware:
     """
     This must be installed after
     :class:`~django.contrib.auth.middleware.AuthenticationMiddleware` and
diff --git a/src/django_otp/models.py b/src/django_otp/models.py
index f09c4a3..d43f224 100644
--- a/src/django_otp/models.py
+++ b/src/django_otp/models.py
@@ -1,7 +1,3 @@
-from __future__ import absolute_import, division, print_function, unicode_literals
-
-import six
-
 from django.apps import apps
 from django.conf import settings
 from django.core.exceptions import ObjectDoesNotExist
@@ -77,16 +73,10 @@ class Device(models.Model):
 
     objects = DeviceManager()
 
-    class Meta(object):
+    class Meta:
         abstract = True
 
     def __str__(self):
-        if six.PY3:
-            return self.__unicode__()
-        else:
-            return self.__unicode__().encode('utf-8')
-
-    def __unicode__(self):
         try:
             user = self.user
         except ObjectDoesNotExist:
@@ -256,7 +246,7 @@ def verify_is_allowed(self):
                          'failure_count': self.throttling_failure_count,
                          })
 
-        return super(ThrottlingMixin, self).verify_is_allowed()
+        return super().verify_is_allowed()
 
     def throttle_reset(self, commit=True):
         """
diff --git a/src/django_otp/oath.py b/src/django_otp/oath.py
index 31b2356..3e8aa80 100644
--- a/src/django_otp/oath.py
+++ b/src/django_otp/oath.py
@@ -1,19 +1,8 @@
-from __future__ import absolute_import, division, print_function, unicode_literals
-
 from hashlib import sha1
 import hmac
 from struct import pack
 from time import time
 
-import six
-
-
-if six.PY3:
-    iterbytes = iter
-else:
-    def iterbytes(buf):
-        return (ord(b) for b in buf)
-
 
 def hotp(key, counter, digits=6):
     """
@@ -43,7 +32,7 @@ def hotp(key, counter, digits=6):
     """
     msg = pack(b'>Q', counter)
     hs = hmac.new(key, msg, sha1).digest()
-    hs = list(iterbytes(hs))
+    hs = list(iter(hs))
 
     offset = hs[19] & 0x0f
     bin_code = (hs[offset] & 0x7f) << 24 | hs[offset + 1] << 16 | hs[offset + 2] << 8 | hs[offset + 3]
@@ -87,7 +76,7 @@ def totp(key, step=30, t0=0, digits=6, drift=0):
     return TOTP(key, step, t0, digits, drift).token()
 
 
-class TOTP(object):
+class TOTP:
     """
     An alternate TOTP interface.
 
diff --git a/src/django_otp/plugins/otp_email/admin.py b/src/django_otp/plugins/otp_email/admin.py
index 438ff8e..486a5cb 100644
--- a/src/django_otp/plugins/otp_email/admin.py
+++ b/src/django_otp/plugins/otp_email/admin.py
@@ -1,5 +1,3 @@
-from __future__ import absolute_import, division, print_function, unicode_literals
-
 from django.contrib import admin
 from django.contrib.admin.sites import AlreadyRegistered
 
diff --git a/src/django_otp/plugins/otp_email/conf.py b/src/django_otp/plugins/otp_email/conf.py
index 237a31d..d9114ea 100644
--- a/src/django_otp/plugins/otp_email/conf.py
+++ b/src/django_otp/plugins/otp_email/conf.py
@@ -1,11 +1,7 @@
-from __future__ import absolute_import, division, print_function, unicode_literals
-
-from six import iteritems
-
 import django.conf
 
 
-class OTPEmailSettings(object):
+class OTPEmailSettings:
     """
     This is a simple class to take the place of the global settings object. An
     instance will contain all of our settings as attributes, with default values
@@ -21,7 +17,7 @@ def __init__(self):
         Loads our settings from django.conf.settings, applying defaults for any
         that are omitted.
         """
-        for name, default in iteritems(self.defaults):
+        for name, default in self.defaults.items():
             value = getattr(django.conf.settings, name, default)
             setattr(self, name, value)
 
diff --git a/src/django_otp/plugins/otp_email/migrations/0001_initial.py b/src/django_otp/plugins/otp_email/migrations/0001_initial.py
index 376393f..813a5ba 100644
--- a/src/django_otp/plugins/otp_email/migrations/0001_initial.py
+++ b/src/django_otp/plugins/otp_email/migrations/0001_initial.py
@@ -1,6 +1,3 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.conf import settings
 from django.db import migrations, models
 
diff --git a/src/django_otp/plugins/otp_email/models.py b/src/django_otp/plugins/otp_email/models.py
index afa0aa6..a09c246 100644
--- a/src/django_otp/plugins/otp_email/models.py
+++ b/src/django_otp/plugins/otp_email/models.py
@@ -1,11 +1,8 @@
-from __future__ import absolute_import, division, print_function, unicode_literals
-
 from binascii import unhexlify
 
 from django.core.mail import send_mail
 from django.db import models
 from django.template.loader import render_to_string
-from django.utils.encoding import force_text
 
 from django_otp.models import Device
 from django_otp.oath import totp
@@ -15,7 +12,7 @@
 
 
 def default_key():
-    return force_text(random_hex(20))
+    return random_hex(20)
 
 
 def key_validator(value):
diff --git a/src/django_otp/plugins/otp_email/tests.py b/src/django_otp/plugins/otp_email/tests.py
index 4810d37..2c921e9 100644
--- a/src/django_otp/plugins/otp_email/tests.py
+++ b/src/django_otp/plugins/otp_email/tests.py
@@ -1,5 +1,3 @@
-from __future__ import absolute_import, division, print_function, unicode_literals
-
 from django.core import mail
 from django.db import IntegrityError
 from django.test.utils import override_settings
diff --git a/src/django_otp/plugins/otp_hotp/admin.py b/src/django_otp/plugins/otp_hotp/admin.py
index 091854f..9ebafc0 100644
--- a/src/django_otp/plugins/otp_hotp/admin.py
+++ b/src/django_otp/plugins/otp_hotp/admin.py
@@ -1,5 +1,3 @@
-from __future__ import absolute_import, division, print_function, unicode_literals
-
 from django.conf.urls import url
 from django.contrib import admin
 from django.contrib.admin.sites import AlreadyRegistered
@@ -40,7 +38,7 @@ class HOTPDeviceAdmin(admin.ModelAdmin):
     radio_fields = {'digits': admin.HORIZONTAL}
 
     def get_queryset(self, request):
-        queryset = super(HOTPDeviceAdmin, self).get_queryset(request)
+        queryset = super().get_queryset(request)
         queryset = queryset.select_related('user')
 
         return queryset
@@ -67,7 +65,7 @@ def get_urls(self):
         urls = [
             url(r'^(?P<pk>\d+)/config/$', self.admin_site.admin_view(self.config_view), name='otp_hotp_hotpdevice_config'),
             url(r'^(?P<pk>\d+)/qrcode/$', self.admin_site.admin_view(self.qrcode_view), name='otp_hotp_hotpdevice_qrcode'),
-        ] + super(HOTPDeviceAdmin, self).get_urls()
+        ] + super().get_urls()
 
         return urls
 
diff --git a/src/django_otp/plugins/otp_hotp/migrations/0001_initial.py b/src/django_otp/plugins/otp_hotp/migrations/0001_initial.py
index aa04deb..9bb81a5 100644
--- a/src/django_otp/plugins/otp_hotp/migrations/0001_initial.py
+++ b/src/django_otp/plugins/otp_hotp/migrations/0001_initial.py
@@ -1,6 +1,3 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.conf import settings
 from django.db import migrations, models
 
diff --git a/src/django_otp/plugins/otp_hotp/models.py b/src/django_otp/plugins/otp_hotp/models.py
index da20f9e..b4185f1 100644
--- a/src/django_otp/plugins/otp_hotp/models.py
+++ b/src/django_otp/plugins/otp_hotp/models.py
@@ -1,14 +1,9 @@
-from __future__ import absolute_import, division, print_function, unicode_literals
-
 from base64 import b32encode
 from binascii import unhexlify
-
-from six import string_types
-from six.moves.urllib.parse import quote, urlencode
+from urllib.parse import quote, urlencode
 
 from django.conf import settings
 from django.db import models
-from django.utils.encoding import force_text
 
 from django_otp.models import Device, ThrottlingMixin
 from django_otp.oath import hotp
@@ -16,7 +11,7 @@
 
 
 def default_key():
-    return force_text(random_hex(20))
+    return random_hex(20)
 
 
 def key_validator(value):
@@ -113,7 +108,7 @@ def config_url(self):
         urlencoded_params = urlencode(params)
 
         issuer = getattr(settings, 'OTP_HOTP_ISSUER', None)
-        if isinstance(issuer, string_types) and (issuer != ''):
+        if isinstance(issuer, str) and (issuer != ''):
             issuer = issuer.replace(':', '')
             label = '{}:{}'.format(issuer, label)
             urlencoded_params += '&issuer={}'.format(quote(issuer))  # encode issuer as per RFC 3986, not quote_plus
diff --git a/src/django_otp/plugins/otp_hotp/tests.py b/src/django_otp/plugins/otp_hotp/tests.py
index 21a0b54..18afdfd 100644
--- a/src/django_otp/plugins/otp_hotp/tests.py
+++ b/src/django_otp/plugins/otp_hotp/tests.py
@@ -1,8 +1,5 @@
-from __future__ import absolute_import, division, print_function, unicode_literals
-
 from datetime import timedelta
-
-from six.moves.urllib.parse import parse_qs, urlsplit
+from urllib.parse import parse_qs, urlsplit
 
 from freezegun import freeze_time
 
diff --git a/src/django_otp/plugins/otp_static/admin.py b/src/django_otp/plugins/otp_static/admin.py
index 88c0765..15714fe 100644
--- a/src/django_otp/plugins/otp_static/admin.py
+++ b/src/django_otp/plugins/otp_static/admin.py
@@ -1,5 +1,3 @@
-from __future__ import absolute_import, division, print_function, unicode_literals
-
 from django.contrib import admin
 from django.contrib.admin.sites import AlreadyRegistered
 
diff --git a/src/django_otp/plugins/otp_static/lib.py b/src/django_otp/plugins/otp_static/lib.py
index e52aeca..e0a1ab7 100644
--- a/src/django_otp/plugins/otp_static/lib.py
+++ b/src/django_otp/plugins/otp_static/lib.py
@@ -1,5 +1,3 @@
-from __future__ import absolute_import, division, print_function, unicode_literals
-
 from django.contrib.auth import get_user_model
 
 from .models import StaticDevice, StaticToken
diff --git a/src/django_otp/plugins/otp_static/management/commands/addstatictoken.py b/src/django_otp/plugins/otp_static/management/commands/addstatictoken.py
index cb72e3d..500d0e6 100644
--- a/src/django_otp/plugins/otp_static/management/commands/addstatictoken.py
+++ b/src/django_otp/plugins/otp_static/management/commands/addstatictoken.py
@@ -1,9 +1,7 @@
-from __future__ import absolute_import, division, print_function, unicode_literals
-
 from textwrap import fill
 
 from django.core.management.base import BaseCommand, CommandError
-from django.utils.encoding import force_text
+from django.utils.encoding import force_str
 
 from django_otp.plugins.otp_static.lib import add_static_token, get_user_model
 
@@ -25,4 +23,4 @@ def handle(self, *args, **options):
         except get_user_model().DoesNotExist:
             raise CommandError('User "{0}" does not exist.'.format(username))
 
-        self.stdout.write(force_text(statictoken.token))
+        self.stdout.write(force_str(statictoken.token))
diff --git a/src/django_otp/plugins/otp_static/migrations/0001_initial.py b/src/django_otp/plugins/otp_static/migrations/0001_initial.py
index 83d1198..c96afe0 100644
--- a/src/django_otp/plugins/otp_static/migrations/0001_initial.py
+++ b/src/django_otp/plugins/otp_static/migrations/0001_initial.py
@@ -1,6 +1,3 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.conf import settings
 from django.db import migrations, models
 
diff --git a/src/django_otp/plugins/otp_static/models.py b/src/django_otp/plugins/otp_static/models.py
index 65c21d4..3afcf43 100644
--- a/src/django_otp/plugins/otp_static/models.py
+++ b/src/django_otp/plugins/otp_static/models.py
@@ -1,5 +1,3 @@
-from __future__ import absolute_import, division, print_function, unicode_literals
-
 from base64 import b32encode
 from os import urandom
 
diff --git a/src/django_otp/plugins/otp_static/tests.py b/src/django_otp/plugins/otp_static/tests.py
index 9c4a930..9da2961 100644
--- a/src/django_otp/plugins/otp_static/tests.py
+++ b/src/django_otp/plugins/otp_static/tests.py
@@ -1,5 +1,3 @@
-from __future__ import absolute_import, division, print_function, unicode_literals
-
 from django.db import IntegrityError
 
 from django_otp.forms import OTPAuthenticationForm
diff --git a/src/django_otp/plugins/otp_totp/admin.py b/src/django_otp/plugins/otp_totp/admin.py
index 9839226..7e62f0f 100644
--- a/src/django_otp/plugins/otp_totp/admin.py
+++ b/src/django_otp/plugins/otp_totp/admin.py
@@ -1,5 +1,3 @@
-from __future__ import absolute_import, division, print_function, unicode_literals
-
 from django.conf.urls import url
 from django.contrib import admin
 from django.contrib.admin.sites import AlreadyRegistered
@@ -40,7 +38,7 @@ class TOTPDeviceAdmin(admin.ModelAdmin):
     radio_fields = {'digits': admin.HORIZONTAL}
 
     def get_queryset(self, request):
-        queryset = super(TOTPDeviceAdmin, self).get_queryset(request)
+        queryset = super().get_queryset(request)
         queryset = queryset.select_related('user')
 
         return queryset
@@ -67,7 +65,7 @@ def get_urls(self):
         urls = [
             url(r'^(?P<pk>\d+)/config/$', self.admin_site.admin_view(self.config_view), name='otp_totp_totpdevice_config'),
             url(r'^(?P<pk>\d+)/qrcode/$', self.admin_site.admin_view(self.qrcode_view), name='otp_totp_totpdevice_qrcode'),
-        ] + super(TOTPDeviceAdmin, self).get_urls()
+        ] + super().get_urls()
 
         return urls
 
diff --git a/src/django_otp/plugins/otp_totp/migrations/0001_initial.py b/src/django_otp/plugins/otp_totp/migrations/0001_initial.py
index aa11f02..59b3609 100644
--- a/src/django_otp/plugins/otp_totp/migrations/0001_initial.py
+++ b/src/django_otp/plugins/otp_totp/migrations/0001_initial.py
@@ -1,6 +1,3 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.conf import settings
 from django.db import migrations, models
 
diff --git a/src/django_otp/plugins/otp_totp/models.py b/src/django_otp/plugins/otp_totp/models.py
index 694b191..f1ebc19 100644
--- a/src/django_otp/plugins/otp_totp/models.py
+++ b/src/django_otp/plugins/otp_totp/models.py
@@ -1,15 +1,10 @@
-from __future__ import absolute_import, division, print_function, unicode_literals
-
 from base64 import b32encode
 from binascii import unhexlify
+from urllib.parse import quote, urlencode
 import time
 
-from six import string_types
-from six.moves.urllib.parse import quote, urlencode
-
 from django.conf import settings
 from django.db import models
-from django.utils.encoding import force_text
 
 from django_otp.models import Device, ThrottlingMixin
 from django_otp.oath import TOTP
@@ -17,7 +12,7 @@
 
 
 def default_key():
-    return force_text(random_hex(20))
+    return random_hex(20)
 
 
 def key_validator(value):
@@ -141,7 +136,7 @@ def config_url(self):
         urlencoded_params = urlencode(params)
 
         issuer = getattr(settings, 'OTP_TOTP_ISSUER', None)
-        if isinstance(issuer, string_types) and (issuer != ''):
+        if isinstance(issuer, str) and (issuer != ''):
             issuer = issuer.replace(':', '')
             label = '{}:{}'.format(issuer, label)
             urlencoded_params += '&issuer={}'.format(quote(issuer))  # encode issuer as per RFC 3986, not quote_plus
diff --git a/src/django_otp/plugins/otp_totp/tests.py b/src/django_otp/plugins/otp_totp/tests.py
index dad8a37..fad4c8d 100644
--- a/src/django_otp/plugins/otp_totp/tests.py
+++ b/src/django_otp/plugins/otp_totp/tests.py
@@ -1,9 +1,6 @@
-from __future__ import absolute_import, division, print_function, unicode_literals
-
 from datetime import timedelta
 from time import time
-
-from six.moves.urllib.parse import parse_qs, urlsplit
+from urllib.parse import parse_qs, urlsplit
 
 from freezegun import freeze_time
 
diff --git a/src/django_otp/tests.py b/src/django_otp/tests.py
index 919b909..7e8b374 100644
--- a/src/django_otp/tests.py
+++ b/src/django_otp/tests.py
@@ -1,13 +1,10 @@
-from __future__ import absolute_import, division, print_function, unicode_literals
-
 from doctest import DocTestSuite
 import pickle
 import unittest
 
-import django
 from django.contrib.auth import get_user_model
 from django.db import IntegrityError
-import django.test
+from django.test import RequestFactory, TestCase as DjangoTestCase
 
 from django_otp import DEVICE_ID_SESSION_KEY, oath, util
 from django_otp.middleware import OTPMiddleware
@@ -23,13 +20,13 @@ def load_tests(loader, tests, pattern):
     return suite
 
 
-class TestCase(django.test.TestCase):
+class TestCase(DjangoTestCase):
     """
     Utilities for dealing with custom user models.
     """
     @classmethod
     def setUpClass(cls):
-        super(TestCase, cls).setUpClass()
+        super().setUpClass()
 
         cls.User = get_user_model()
         cls.USERNAME_FIELD = cls.User.USERNAME_FIELD
@@ -46,7 +43,7 @@ def create_user(self, username, password):
 
 class OTPMiddlewareTestCase(TestCase):
     def setUp(self):
-        self.factory = django.test.RequestFactory()
+        self.factory = RequestFactory()
         try:
             self.alice = self.create_user('alice', 'password')
             self.bob = self.create_user('bob', 'password')
diff --git a/src/django_otp/util.py b/src/django_otp/util.py
index 5aeb031..53b345b 100644
--- a/src/django_otp/util.py
+++ b/src/django_otp/util.py
@@ -1,10 +1,6 @@
-from __future__ import absolute_import, division, print_function, unicode_literals
-
-from binascii import hexlify, unhexlify
+from binascii import unhexlify
 from os import urandom
 
-import six
-
 from django.core.exceptions import ValidationError
 
 
@@ -16,7 +12,7 @@ def hex_validator(length=0):
         def key_validator(value):
             return hex_validator(20)(value)
 
-        key = models.CharField(max_length=40, validators=[key_validator], help_text=u'A hex-encoded 20-byte secret key')
+        key = models.CharField(max_length=40, validators=[key_validator], help_text='A hex-encoded 20-byte secret key')
 
     :param int length: If greater than 0, validation will fail unless the
         decoded value is exactly this number of bytes.
@@ -36,7 +32,7 @@ def key_validator(value):
     """
     def _validator(value):
         try:
-            if isinstance(value, six.text_type):
+            if isinstance(value, str):
                 value = value.encode()
 
             unhexlify(value)
@@ -58,7 +54,7 @@ def random_hex(length=20):
     :param int length: The number of (decoded) bytes to return.
 
     :returns: A string of hex digits.
-    :rtype: bytes
+    :rtype: str
 
     """
-    return hexlify(urandom(length))
+    return urandom(length).hex()
diff --git a/src/django_otp/views.py b/src/django_otp/views.py
index 54bd131..eebecdc 100644
--- a/src/django_otp/views.py
+++ b/src/django_otp/views.py
@@ -1,5 +1,3 @@
-from __future__ import absolute_import, division, print_function, unicode_literals
-
 from functools import partial
 
 from django.contrib.auth import BACKEND_SESSION_KEY
@@ -42,7 +40,7 @@ def form_valid(self, form):
         if not hasattr(user, 'backend'):
             user.backend = self.request.session[BACKEND_SESSION_KEY]
 
-        return super(LoginView, self).form_valid(form)
+        return super().form_valid(form)
 
 
 # Backwards compatibility.
diff --git a/test/test_project/backends.py b/test/test_project/backends.py
index a4e1bca..3da186a 100644
--- a/test/test_project/backends.py
+++ b/test/test_project/backends.py
@@ -1,7 +1,4 @@
-from __future__ import absolute_import, division, print_function, unicode_literals
-
-
-class DummyBackend(object):
+class DummyBackend:
     def authenticate(self, request):
         return None
 
diff --git a/test/test_project/settings.py b/test/test_project/settings.py
index e0a9ddb..15c503f 100644
--- a/test/test_project/settings.py
+++ b/test/test_project/settings.py
@@ -1,7 +1,5 @@
 # django-otp test project
 
-from __future__ import absolute_import, division, print_function, unicode_literals
-
 from os.path import abspath, dirname, join
 
 
diff --git a/test/test_project/urls.py b/test/test_project/urls.py
index ac13dd5..c338b3c 100644
--- a/test/test_project/urls.py
+++ b/test/test_project/urls.py
@@ -1,5 +1,3 @@
-from __future__ import absolute_import, division, print_function, unicode_literals
-
 from django.conf.urls import url
 from django.contrib import admin
 import django.contrib.auth.views
diff --git a/tox.ini b/tox.ini
index 3f9f069..5d66de9 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,6 +1,6 @@
 [tox]
 envlist = static
-          py{27,37}-django111
+          py{37}-django111
           py{35,36}-django22
           py{37,38}-django30
           coverage
@@ -9,7 +9,6 @@ envlist = static
 setenv = PYTHONPATH = {env:PYTHONPATH:}{:}{toxinidir}/test
          DJANGO_SETTINGS_MODULE = test_project.settings
 deps = freezegun
-       mock ; python_version < "3.0"
        django111: Django==1.11.*
        django22: Django==2.2.*
        django30: Django==3.0.*