diff --git a/sshuttle/helpers.py b/sshuttle/helpers.py
index 6c8ab82..a62bea9 100644
--- a/sshuttle/helpers.py
+++ b/sshuttle/helpers.py
@@ -5,8 +5,6 @@ import errno
 logprefix = ''
 verbose = 0
 
-binary_type = bytes
-
 
 def b(s):
     return s.encode("ASCII")
diff --git a/sshuttle/ssnet.py b/sshuttle/ssnet.py
index e7f668b..7604093 100644
--- a/sshuttle/ssnet.py
+++ b/sshuttle/ssnet.py
@@ -5,7 +5,7 @@ import errno
 import select
 import os
 
-from sshuttle.helpers import b, binary_type, log, debug1, debug2, debug3, Fatal
+from sshuttle.helpers import b, log, debug1, debug2, debug3, Fatal
 
 MAX_CHANNEL = 65535
 LATENCY_BUFFER_SIZE = 32768
@@ -382,7 +382,7 @@ class Mux(Handler):
         # log('outbuf: %d %r\n' % (self.amount_queued(), ob))
 
     def send(self, channel, cmd, data):
-        assert isinstance(data, binary_type)
+        assert isinstance(data, bytes)
         assert len(data) <= 65535
         p = struct.pack('!ccHHH', b('S'), b('S'), channel, cmd, len(data)) \
             + data
diff --git a/tests/conftest.py b/tests/conftest.py
deleted file mode 100644
index 95052f1..0000000
--- a/tests/conftest.py
+++ /dev/null
@@ -1,7 +0,0 @@
-import sys
-
-good_python = sys.version_info >= (3, 5)
-
-collect_ignore = []
-if not good_python:
-    collect_ignore.append("client")