diff --git a/wagtail/tests/utils/assert_logs.py b/wagtail/tests/utils/assert_logs.py
deleted file mode 100644
index 21bffcdc3..000000000
--- a/wagtail/tests/utils/assert_logs.py
+++ /dev/null
@@ -1,83 +0,0 @@
-import logging
-from collections import namedtuple
-
-
-# Implementation of TestCase.assertLogs for pre-3.4 Python versions.
-# Borrowed from https://github.com/django/django/pull/3467/commits/1b4f10963628bb68246c193f1124a1f7b6e4c696
-
-class _BaseTestCaseContext:
-    def __init__(self, test_case):
-        self.test_case = test_case
-
-    def _raiseFailure(self, standardMsg):
-        msg = self.test_case._formatMessage(self.msg, standardMsg)
-        raise self.test_case.failureException(msg)
-
-
-_LoggingWatcher = namedtuple("_LoggingWatcher", ["records", "output"])
-
-
-class _CapturingHandler(logging.Handler):
-    """
-    A logging handler capturing all (raw and formatted) logging output.
-    """
-
-    def __init__(self):
-        logging.Handler.__init__(self)
-        self.watcher = _LoggingWatcher([], [])
-
-    def flush(self):
-        pass
-
-    def emit(self, record):
-        self.watcher.records.append(record)
-        msg = self.format(record)
-        self.watcher.output.append(msg)
-
-
-class _AssertLogsContext(_BaseTestCaseContext):
-    """A context manager used to implement TestCase.assertLogs()."""
-
-    # original format is "%(levelname)s:%(name)s:%(message)s"
-    LOGGING_FORMAT = "%(message)s"
-
-    def __init__(self, test_case, logger_name, level):
-        _BaseTestCaseContext.__init__(self, test_case)
-        self.logger_name = logger_name
-        if level:
-            if getattr(logging, '_nameToLevel', False):
-                self.level = logging._nameToLevel.get(level, level)
-            else:
-                self.level = logging._levelNames.get(level, level)
-        else:
-            self.level = logging.INFO
-        self.msg = None
-
-    def __enter__(self):
-        if isinstance(self.logger_name, logging.Logger):
-            logger = self.logger = self.logger_name
-        else:
-            logger = self.logger = logging.getLogger(self.logger_name)
-        formatter = logging.Formatter(self.LOGGING_FORMAT)
-        handler = _CapturingHandler()
-        handler.setFormatter(formatter)
-        self.watcher = handler.watcher
-        self.old_handlers = logger.handlers[:]
-        self.old_level = logger.level
-        self.old_propagate = logger.propagate
-        logger.handlers = [handler]
-        logger.setLevel(self.level)
-        logger.propagate = False
-        return handler.watcher
-
-    def __exit__(self, exc_type, exc_value, tb):
-        self.logger.handlers = self.old_handlers
-        self.logger.propagate = self.old_propagate
-        self.logger.setLevel(self.old_level)
-        if exc_type is not None:
-            # let unexpected exceptions pass through
-            return False
-        if len(self.watcher.records) == 0:
-            self._raiseFailure(
-                "no logs of level {} or higher triggered on {}"
-                .format(logging.getLevelName(self.level), self.logger.name))
diff --git a/wagtail/tests/utils/wagtail_tests.py b/wagtail/tests/utils/wagtail_tests.py
index 7b96b8405..f6dc31912 100644
--- a/wagtail/tests/utils/wagtail_tests.py
+++ b/wagtail/tests/utils/wagtail_tests.py
@@ -1,12 +1,9 @@
-import sys
 import warnings
 from contextlib import contextmanager
 
 from django.contrib.auth import get_user_model
 from django.test.testcases import assert_and_parse_html
 
-from .assert_logs import _AssertLogsContext
-
 
 class WagtailTestUtils:
 
@@ -56,45 +53,6 @@ class WagtailTestUtils:
                     line=w.line
                 )
 
-    # borrowed from https://github.com/django/django/commit/9f427617e4559012e1c2fd8fce46cbe225d8515d
-    @staticmethod
-    def reset_warning_registry():
-        """
-        Clear warning registry for all modules. This is required in some tests
-        because of a bug in Python that prevents warnings.simplefilter("always")
-        from always making warnings appear: http://bugs.python.org/issue4180
-
-        The bug was fixed in Python 3.4.2.
-        """
-        key = "__warningregistry__"
-        for mod in list(sys.modules.values()):
-            if hasattr(mod, key):
-                getattr(mod, key).clear()
-
-    # Configuring LOGGING_FORMAT is not possible without subclassing
-    # unittest.TestCase, so use this implementation even on Python 3.4
-    def assertLogs(self, logger=None, level=None):
-        """Fail unless a log message of level *level* or higher is emitted
-        on *logger_name* or its children.  If omitted, *level* defaults to
-        INFO and *logger* defaults to the root logger.
-
-        This method must be used as a context manager, and will yield
-        a recording object with two attributes: `output` and `records`.
-        At the end of the context manager, the `output` attribute will
-        be a list of the matching formatted log messages and the
-        `records` attribute will be a list of the corresponding LogRecord
-        objects.
-
-        Example::
-
-            with self.assertLogs('foo', level='INFO') as cm:
-                logging.getLogger('foo').info('first message')
-                logging.getLogger('foo.bar').error('second message')
-            self.assertEqual(cm.output, ['INFO:foo:first message',
-                                         'ERROR:foo.bar:second message'])
-        """
-        return _AssertLogsContext(self, logger, level)
-
     @contextmanager
     def register_hook(self, hook_name, fn, order=0):
         from wagtail.core import hooks