diff --git a/prog/server.py b/prog/server.py
index acd9b7bc85492fa12560168b3ea56f6107bd41ec..4b326ba983462fd4c74a3d2eac206085e839fc6f 100644
--- a/prog/server.py
+++ b/prog/server.py
@@ -19,14 +19,14 @@ class MainServer(communication.FuncCaller):
     async def _get_download_server(self):
         if self._download_server is None:
             import download_server
-            s = await UnixSocket().connect("sockets/download_server")
+            s = await communication.UnixSocket().connect("sockets/download_server")
             self._download_server = download_server.DownloadServer(s)
         return self._download_server
 
     async def _get_preprocess_server(self):
         if self._preprocess_server is None:
             import preprocess
-            s = await UnixSocket().connect("sockets/preprocess_server")
+            s = await communication.UnixSocket().connect("sockets/preprocess_server")
             self._preprocess_server = preprocess.PreprocessServer(s)
         return self._preprocess_server