diff --git a/.gitignore b/.gitignore
index d649848..32b86d4 100644
--- a/.gitignore
+++ b/.gitignore
@@ -8,6 +8,7 @@ sword2.egg-info/
 *.py~
 *.conf
 
+.tox
 .coverage
 htmlcov/
 
diff --git a/setup.py b/setup.py
index b43fb33..eae82d4 100644
--- a/setup.py
+++ b/setup.py
@@ -17,11 +17,17 @@
         "Intended Audience :: Developers",
         "Intended Audience :: Information Technology",
         "Intended Audience :: Science/Research",
-	"License :: OSI Approved :: Apache Software License",
-	"Natural Language :: English",
+        "License :: OSI Approved :: Apache Software License",
+        "Natural Language :: English",
         "Operating System :: OS Independent",
-	"Programming Language :: Python :: 2 :: Only",
-	"Topic :: Communications",
+        "Programming Language :: Python :: 2",
+        "Programming Language :: Python :: 2.7",
+        "Programming Language :: Python :: 3",
+        "Programming Language :: Python :: 3.6",
+        "Programming Language :: Python :: 3.7",
+        "Programming Language :: Python :: 3.8",
+        "Programming Language :: Python :: 3.9",
+        "Topic :: Communications",
         "Topic :: Internet",
         "Topic :: Internet :: WWW/HTTP",
         "Topic :: Software Development :: Libraries :: Python Modules",
diff --git a/tests/databank/test_databank.py b/tests/databank/test_databank.py
index 5b75a41..54d7c2f 100644
--- a/tests/databank/test_databank.py
+++ b/tests/databank/test_databank.py
@@ -1,7 +1,7 @@
 import uuid
 from . import TestController
 from sword2 import Connection, Entry, Error_Document, Atom_Sword_Statement, Ore_Sword_Statement
-from sword2.compatible_libs import etree
+from lxml import etree
 
 PACKAGE = "tests/databank/example.zip"
 PACKAGE_MIME = "application/zip"
diff --git a/tests/functional/test_connection.py b/tests/functional/test_connection.py
index 72f82bd..bb6263d 100644
--- a/tests/functional/test_connection.py
+++ b/tests/functional/test_connection.py
@@ -1,7 +1,8 @@
+import json
+
 from . import TestController
 
 from sword2 import Connection
-from sword2.compatible_libs import json
 
 long_service_doc = '''<?xml version="1.0" ?>
 <service xmlns:dcterms="http://purl.org/dc/terms/"
diff --git a/tests/functional/test_service_document.py b/tests/functional/test_service_document.py
index 63fe6c3..78347ff 100644
--- a/tests/functional/test_service_document.py
+++ b/tests/functional/test_service_document.py
@@ -1,7 +1,8 @@
+import json
+
 from . import TestController
 
 from sword2 import SDCollection, ServiceDocument
-from sword2.compatible_libs import json
 
 class TestSDCollection(TestController):
     def test_01_blank_init(self):
diff --git a/tests/http/test_sss.py b/tests/http/test_sss.py
index 1c1d7c3..97d38aa 100644
--- a/tests/http/test_sss.py
+++ b/tests/http/test_sss.py
@@ -1,8 +1,9 @@
+import json
+
 from . import TestController
 
 from sword2 import Connection, Entry
 from sword2.exceptions import PackagingFormatNotAvailable
-from sword2.compatible_libs import json
 
 #SSS_PY_URL="http://sword-app.svn.sourceforge.net/viewvc/sword-app/sss/trunk/sss.py?revision=HEAD"
 SSS_PY_URL="https://raw.githubusercontent.com/OA-DeepGreen/Simple-Sword-Server/master/sss/sss-1.0.py"
diff --git a/tests/pylons/test_pylons.py b/tests/pylons/test_pylons.py
index d0bb8f2..66f9369 100644
--- a/tests/pylons/test_pylons.py
+++ b/tests/pylons/test_pylons.py
@@ -1,6 +1,7 @@
+from lxml import etree
+
 from . import TestController
 from sword2 import Connection, Entry, Error_Document, Atom_Sword_Statement, Ore_Sword_Statement
-from sword2.compatible_libs import etree
 
 PACKAGE = "tests/spec/example.zip"
 PACKAGE_MIME = "application/zip"
diff --git a/tests/spec/test_spec.py b/tests/spec/test_spec.py
index d18c317..c3de2a2 100644
--- a/tests/spec/test_spec.py
+++ b/tests/spec/test_spec.py
@@ -1,6 +1,7 @@
+from lxml import etree
+
 from . import TestController
 from sword2 import Connection, Entry, Error_Document, Atom_Sword_Statement, Ore_Sword_Statement
-from sword2.compatible_libs import etree
 
 PACKAGE = "tests/spec/example.zip"
 PACKAGE_MIME = "application/zip"
diff --git a/tests/urllib2tests/test_urllib2.py b/tests/urllib2tests/test_urllib2.py
index 96ee788..4d0e5ef 100644
--- a/tests/urllib2tests/test_urllib2.py
+++ b/tests/urllib2tests/test_urllib2.py
@@ -1,6 +1,7 @@
+from lxml import etree
+
 from . import TestController
 from sword2 import Connection, Entry, Error_Document, Atom_Sword_Statement, Ore_Sword_Statement, UrlLib2Layer
-from sword2.compatible_libs import etree
 
 PACKAGE = "tests/spec/example.zip"
 PACKAGE_MIME = "application/zip"
diff --git a/tox.ini b/tox.ini
index 4479b28..01201b6 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,5 +1,5 @@
 [tox]
-envlist = py37, py38, py39
+envlist = py{36,37,38,39}
 [testenv]
 deps=httplib2
      lxml