diff --git a/.travis.yml b/.travis.yml
index e69ccf5..91154e6 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -5,14 +5,14 @@ sudo: false
 cache: pip
 
 python:
-  - 2.7
-  - 3.5
   - 3.6
   - 3.7
+  - 3.8
+  - 3.9
   - "nightly"
 
 allow_failures:
-  # Just tests how PyInstaller performs with upcoming Python 3.8
+  # Just tests how PyInstaller performs with upcoming Python 3.10
   - python: "nightly"
 
 # Install dependencies.
@@ -28,4 +28,4 @@ install:
   - pip install -r tests/requirements.txt | cat
 
 script:
-  - py.test -vv
+  - pytest -vv
diff --git a/CHANGES.rst b/CHANGES.rst
index 4eb2fef..ca746ac 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -4,7 +4,10 @@ Changelog
 0.5 (unreleased)
 ----------------
 
-- Nothing changed yet.
+* Drop support for Python 2 and 3.5
+
+* Fix ``assertDictContainsSubset``. On Python 3, the replacement would raise
+  a TypeError if the dictionary contained non-string keys.
 
 
 0.4 (2019-06-30)
diff --git a/DEVELOPER.rst b/DEVELOPER.rst
index 2819ac6..8fc32d2 100644
--- a/DEVELOPER.rst
+++ b/DEVELOPER.rst
@@ -8,7 +8,7 @@ https://travis-ci.org/pytest-dev/unittest2pytest/.
 Prior to pushing a pull-request to github, please test locally::
 
   pip install tox pytest
-  tox  # or tox -e py27,py33,py34
+  tox  # or tox -e py36,py37,py38,py39
 
 
 Version Scheme
@@ -54,7 +54,7 @@ Full Release Process
 
 4. Be sure that the current code passes tests locally::
 
-     tox -e py27,py33,py34
+     tox -e py36,py37,py38,py39
 
 5. Be sure `CI tests
    <https://travis-ci.org/pytest-dev/unittest2pytest/>`_ pass.
diff --git a/setup.py b/setup.py
index ce2848f..154908e 100644
--- a/setup.py
+++ b/setup.py
@@ -43,8 +43,6 @@ def read(filename):
         return open(filename, 'r', encoding='utf-8').read()
 long_description = '\n\n'.join([read('README.rst'),
                                 read('CHANGES.rst')])
-if sys.version_info < (3,):
-    long_description = long_description.encode('utf-8')
 
 
 setup(
@@ -69,15 +67,14 @@ def read(filename):
         "License :: OSI Approved :: GNU General Public License v3 or later (GPLv3+)",
         "Operating System :: OS Independent",
         "Programming Language :: Python",
-        "Programming Language :: Python :: 2",
-        "Programming Language :: Python :: 2.7",
         "Programming Language :: Python :: 3",
-        "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",
         "Topic :: Software Development",
         "Topic :: Utilities",
     ],
-    python_requires=">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*",
+    python_requires=">=3.6",
     zip_safe=False
 )
diff --git a/tests/fixtures/self_assert/assertDictContainsSubset_out.py b/tests/fixtures/self_assert/assertDictContainsSubset_out.py
index a9415f5..07e7f51 100644
--- a/tests/fixtures/self_assert/assertDictContainsSubset_out.py
+++ b/tests/fixtures/self_assert/assertDictContainsSubset_out.py
@@ -2,19 +2,19 @@
 
 class TestDictEqual(TestCase):
     def test_simple(self):
-        assert dict(superset, **{'a: 1'}) == superset
+        assert {**superset, **{'a: 1'}} == superset
 
     def test_simple_msg(self):
-        assert dict({'a: 1'}, **subset) == {'a: 1'}, "This is wrong!"
+        assert {**{'a: 1'}, **subset} == {'a: 1'}, "This is wrong!"
 
     def test_simple_msg2(self):
-        assert dict({'a: 1'}, **subset) == {'a: 1'}, "This is wrong!"
+        assert {**{'a: 1'}, **subset} == {'a: 1'}, "This is wrong!"
 
     def test_line_wrapping(self):
-        assert dict({
+        assert {**{
                 'a': 1,
                 'b': 2,
-            }, **{'b': 2}) == {
+            }, **{'b': 2}} == {
                 'a': 1,
                 'b': 2,
             }, \
diff --git a/tests/test_all_fixes.py b/tests/test_all_fixes.py
index c435554..e10d7b2 100644
--- a/tests/test_all_fixes.py
+++ b/tests/test_all_fixes.py
@@ -1,5 +1,4 @@
 #!/usr/bin/env python
-# -*- coding: utf-8 -*-
 """
 This file is part of test-suite for unittest2pytest.
 """
@@ -22,8 +21,6 @@
 # along with this program. If not, see <http://www.gnu.org/licenses/>.
 #
 
-from __future__ import unicode_literals
-
 __author__ = "Hartmut Goebel <h.goebel@crazy-compilers.com>"
 __copyright__ = "Copyright 2015-2019 by Hartmut Goebel"
 __licence__ = "GNU General Public License version 3 or later (GPLv3+)"
diff --git a/tox.ini b/tox.ini
index 154599b..26d02c1 100644
--- a/tox.ini
+++ b/tox.ini
@@ -4,7 +4,7 @@
 # and then run "tox" from this directory.
 
 [tox]
-envlist = py27, py35, py36, py37
+envlist = py36, py37, py38, py39
 
 [testenv]
 deps =
diff --git a/unittest2pytest/__init__.py b/unittest2pytest/__init__.py
index e63c1a5..4d087ef 100644
--- a/unittest2pytest/__init__.py
+++ b/unittest2pytest/__init__.py
@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 #
 # Copyright 2015-2019 by Hartmut Goebel <h.goebel@crazy-compilers.com>
 #
diff --git a/unittest2pytest/__main__.py b/unittest2pytest/__main__.py
index dfcf051..384f85c 100755
--- a/unittest2pytest/__main__.py
+++ b/unittest2pytest/__main__.py
@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 #
 # Copyright 2015-2019 by Hartmut Goebel <h.goebel@crazy-compilers.com>
 #
diff --git a/unittest2pytest/fixes/fix_remove_class.py b/unittest2pytest/fixes/fix_remove_class.py
index 0fb3b3d..9f0109d 100644
--- a/unittest2pytest/fixes/fix_remove_class.py
+++ b/unittest2pytest/fixes/fix_remove_class.py
@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 """
 fix_remove_class - lib2to3 fix for removing "class Testxxx(TestCase):"
 headers and dedenting the contained code.
diff --git a/unittest2pytest/fixes/fix_self_assert.py b/unittest2pytest/fixes/fix_self_assert.py
index 8000c08..5f0f24f 100644
--- a/unittest2pytest/fixes/fix_self_assert.py
+++ b/unittest2pytest/fixes/fix_self_assert.py
@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 """
 fix_self_assert - lib2to3 fix for replacing assertXXX() method calls
 by their pytest equivalent.
@@ -277,7 +276,7 @@ def get_import_nodes(node):
     'assertTupleEqual':     partial(CompOp, '=='),
     'assertSequenceEqual':  SequenceEqual,
 
-    'assertDictContainsSubset': partial(DualOp, 'dict(\2, **\1) == \2'),
+    'assertDictContainsSubset': partial(DualOp, '{**\2, **\1} == \2'),
     'assertItemsEqual':         partial(DualOp, 'sorted(\1) == sorted(\2)'),
 
     'assertAlmostEqual':    partial(AlmostOp, "==", "<"),
diff --git a/unittest2pytest/utils.py b/unittest2pytest/utils.py
index 9f96200..fa152bb 100644
--- a/unittest2pytest/utils.py
+++ b/unittest2pytest/utils.py
@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 """
 Some utility functions for unittest2pytest.
 """
@@ -27,80 +26,24 @@
 
 
 import inspect
-try:
-    from inspect import Parameter
-except ImportError:
-    # Python 2
-    pass
-from collections import OrderedDict
+from inspect import Parameter
 
 
 class SelfMarker: pass
 
-def __apply_defaults(boundargs):
-    # Backport of Python 3.5 inspect.BoundArgs.apply_defaults()
-    arguments = boundargs.arguments
-    if not arguments:
-        return
-    new_arguments = []
-    for name, param in boundargs.signature.parameters.items():
-        try:
-            new_arguments.append((name, arguments[name]))
-        except KeyError:
-            if param.default is not Parameter.empty:
-                val = param.default
-            elif param.kind is Parameter.VAR_POSITIONAL:
-                val = ()
-            elif param.kind is Parameter.VAR_KEYWORD:
-                val = {}
-            else:
-                # This BoundArguments was likely produced by
-                # Signature.bind_partial().
-                continue
-            new_arguments.append((name, val))
-    boundargs.arguments = OrderedDict(new_arguments)
-
-
 def resolve_func_args(test_func, posargs, kwargs):
-    try:
-        inspect.signature
-    except AttributeError:
-        # Python 2.7
-        posargs.insert(0, SelfMarker)
-        args = inspect.getcallargs(test_func, *posargs, **kwargs)
-
-        assert args['self'] == SelfMarker
-        argspec = inspect.getargspec(test_func)
-        #if not 'Raises' in method:
-        #    assert argspec.varargs is None  # unhandled case
-        #    assert argspec.keywords is None  # unhandled case
-
-        # get the required arguments
-        if argspec.defaults:
-            required_args = argspec.args[1:-len(argspec.defaults)]
-        else:
-            required_args = argspec.args[1:]
-        required_args = [args[argname] for argname in required_args]
-
-    else:
-        sig = inspect.signature(test_func)
-        assert (list(iter(sig.parameters))[0] == 'self')
-        posargs.insert(0, SelfMarker)
-        ba = sig.bind(*posargs, **kwargs)
-        try:
-            ba.apply_defaults
-        except AttributeError:
-            # Python < 3.5
-            __apply_defaults(ba)
-        else:
-            ba.apply_defaults()
-        args = ba.arguments
-        required_args = [n for n,v in sig.parameters.items()
-                         if (v.default is Parameter.empty and
-                             v.kind not in (Parameter.VAR_POSITIONAL, Parameter.VAR_KEYWORD))]
-        assert args['self'] == SelfMarker
-        assert required_args[0] == 'self'
-        del required_args[0], args['self']
-        required_args = [args[n] for n in required_args]
+    sig = inspect.signature(test_func)
+    assert (list(iter(sig.parameters))[0] == 'self')
+    posargs.insert(0, SelfMarker)
+    ba = sig.bind(*posargs, **kwargs)
+    ba.apply_defaults()
+    args = ba.arguments
+    required_args = [n for n,v in sig.parameters.items()
+                        if (v.default is Parameter.empty and
+                            v.kind not in (Parameter.VAR_POSITIONAL, Parameter.VAR_KEYWORD))]
+    assert args['self'] == SelfMarker
+    assert required_args[0] == 'self'
+    del required_args[0], args['self']
+    required_args = [args[n] for n in required_args]
 
     return required_args, args