diff --git a/synapse/util/caches/__init__.py b/synapse/util/caches/__init__.py
index 900575eb3c..7b065b195e 100644
--- a/synapse/util/caches/__init__.py
+++ b/synapse/util/caches/__init__.py
@@ -13,12 +13,12 @@
# See the License for the specific language governing permissions and
# limitations under the License.
-from prometheus_client.core import Gauge, REGISTRY, GaugeMetricFamily
-
import os
-from six.moves import intern
import six
+from six.moves import intern
+
+from prometheus_client.core import REGISTRY, Gauge, GaugeMetricFamily
CACHE_SIZE_FACTOR = float(os.environ.get("SYNAPSE_CACHE_FACTOR", 0.5))
diff --git a/synapse/util/caches/descriptors.py b/synapse/util/caches/descriptors.py
index 65a1042de1..f8a07df6b8 100644
--- a/synapse/util/caches/descriptors.py
+++ b/synapse/util/caches/descriptors.py
@@ -13,10 +13,19 @@
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
+import functools
+import inspect
import logging
+import threading
+from collections import namedtuple
+import six
+from six import itervalues, string_types
+
+from twisted.internet import defer
+
+from synapse.util import logcontext, unwrapFirstError
from synapse.util.async import ObservableDeferred
-from synapse.util import unwrapFirstError, logcontext
from synapse.util.caches import get_cache_factor_for
from synapse.util.caches.lrucache import LruCache
from synapse.util.caches.treecache import TreeCache, iterate_tree_cache_entry
@@ -24,17 +33,6 @@ from synapse.util.stringutils import to_ascii
from . import register_cache
-from twisted.internet import defer
-from collections import namedtuple
-
-import functools
-import inspect
-import threading
-
-from six import string_types, itervalues
-import six
-
-
logger = logging.getLogger(__name__)
diff --git a/synapse/util/caches/dictionary_cache.py b/synapse/util/caches/dictionary_cache.py
index 95793d466d..6c0b5a4094 100644
--- a/synapse/util/caches/dictionary_cache.py
+++ b/synapse/util/caches/dictionary_cache.py
@@ -13,12 +13,13 @@
# See the License for the specific language governing permissions and
# limitations under the License.
-from synapse.util.caches.lrucache import LruCache
-from collections import namedtuple
-from . import register_cache
-import threading
import logging
+import threading
+from collections import namedtuple
+
+from synapse.util.caches.lrucache import LruCache
+from . import register_cache
logger = logging.getLogger(__name__)
diff --git a/synapse/util/caches/expiringcache.py b/synapse/util/caches/expiringcache.py
index ff04c91955..4abca91f6d 100644
--- a/synapse/util/caches/expiringcache.py
+++ b/synapse/util/caches/expiringcache.py
@@ -13,11 +13,10 @@
# See the License for the specific language governing permissions and
# limitations under the License.
-from synapse.util.caches import register_cache
-
-from collections import OrderedDict
import logging
+from collections import OrderedDict
+from synapse.util.caches import register_cache
logger = logging.getLogger(__name__)
diff --git a/synapse/util/caches/lrucache.py b/synapse/util/caches/lrucache.py
index 1c5a982094..b684f24e7b 100644
--- a/synapse/util/caches/lrucache.py
+++ b/synapse/util/caches/lrucache.py
@@ -14,8 +14,8 @@
# limitations under the License.
-from functools import wraps
import threading
+from functools import wraps
from synapse.util.caches.treecache import TreeCache
diff --git a/synapse/util/caches/stream_change_cache.py b/synapse/util/caches/stream_change_cache.py
index 0fb8620001..8637867c6d 100644
--- a/synapse/util/caches/stream_change_cache.py
+++ b/synapse/util/caches/stream_change_cache.py
@@ -13,12 +13,11 @@
# See the License for the specific language governing permissions and
# limitations under the License.
-from synapse.util import caches
-
+import logging
from sortedcontainers import SortedDict
-import logging
+from synapse.util import caches
logger = logging.getLogger(__name__)
|