diff --git a/tests/bitarithm_timings/tests/01-run.py b/tests/bitarithm_timings/tests/01-run.py
index dfc6f446f9106e7c849d1a92d6dfeac085e673c3..bc8f4c236f8962c63dc2d318fa559ca6e69f0c89 100755
--- a/tests/bitarithm_timings/tests/01-run.py
+++ b/tests/bitarithm_timings/tests/01-run.py
@@ -12,6 +12,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def testfunc(child):
     child.expect_exact("Start.")
     child.expect('\+ bitarithm_msb: \d+ iterations per second')
diff --git a/tests/bloom_bytes/tests/01-run.py b/tests/bloom_bytes/tests/01-run.py
index fc4a816117d16651f2134ae75071c509055c5c68..6585ca3487659676785cf74105193d8a5f5690c4 100755
--- a/tests/bloom_bytes/tests/01-run.py
+++ b/tests/bloom_bytes/tests/01-run.py
@@ -12,6 +12,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def testfunc(child):
     child.expect_exact("Testing Bloom filter.")
     child.expect_exact("m: 4096 k: 8")
diff --git a/tests/buttons/tests/01-run.py b/tests/buttons/tests/01-run.py
index 54647e54834d832372c4c844c352cc4c6bfb92be..6037857e9d9208747db9db05b18529f97ac661a9 100755
--- a/tests/buttons/tests/01-run.py
+++ b/tests/buttons/tests/01-run.py
@@ -12,6 +12,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def testfunc(child):
     child.expect_exact("On-board button test")
     index = child.expect([
diff --git a/tests/cbor/tests/01-run.py b/tests/cbor/tests/01-run.py
index bd97513d245dcd62081e0bdef5da0a05386ebd83..c3ec006d31f57e602d5577b7e92bc1dc1d3d9418 100755
--- a/tests/cbor/tests/01-run.py
+++ b/tests/cbor/tests/01-run.py
@@ -14,6 +14,7 @@ import testrunner
 
 ACCEPTED_ERROR = 20
 
+
 def testfunc(child):
     child.expect_exact('Data:')
     child.expect_exact('(uint64_t, 1)')
diff --git a/tests/cpp11_condition_variable/tests/01-run.py b/tests/cpp11_condition_variable/tests/01-run.py
index 3ac6d799f1c1b2fdf33310a9f883e9d8b7eeb49f..5fde64fe278821d4611a279a3b3fcec0ba941a01 100755
--- a/tests/cpp11_condition_variable/tests/01-run.py
+++ b/tests/cpp11_condition_variable/tests/01-run.py
@@ -13,8 +13,8 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
-def testfunc(child):
 
+def testfunc(child):
     child.expect_exact("************ C++ condition_variable test ***********")
     child.expect_exact("Wait with predicate and notify one ...")
     child.expect_exact("Done")
diff --git a/tests/cpp11_mutex/tests/01-run.py b/tests/cpp11_mutex/tests/01-run.py
index 5be11d836abaa3b5ca8509ddb97f164fa55c5923..1646e6adf4fb5fa886781142b9649c52b3583d10 100755
--- a/tests/cpp11_mutex/tests/01-run.py
+++ b/tests/cpp11_mutex/tests/01-run.py
@@ -13,8 +13,8 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
-def testfunc(child):
 
+def testfunc(child):
     child.expect_exact("************ C++ mutex test ***********")
     child.expect_exact("Lock and unlock ...")
     child.expect_exact("Done")
diff --git a/tests/cpp11_thread/tests/01-run.py b/tests/cpp11_thread/tests/01-run.py
index 6636188ea97823465535114a27fcc96508775996..0307f923886a647f0da894fc3bef2a15d2a943dd 100755
--- a/tests/cpp11_thread/tests/01-run.py
+++ b/tests/cpp11_thread/tests/01-run.py
@@ -13,8 +13,8 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
-def testfunc(child):
 
+def testfunc(child):
     child.expect_exact("************ C++ thread test ***********")
     child.expect_exact("Creating one thread and passing an argument ...")
     child.expect_exact("Done")
diff --git a/tests/driver_ds1307/tests/01-run.py b/tests/driver_ds1307/tests/01-run.py
index ab9bdb938f3333ed501b01d3fc983a408253a167..055199ef0f4f2b6fbc913d3129fe211f7fc3ad06 100755
--- a/tests/driver_ds1307/tests/01-run.py
+++ b/tests/driver_ds1307/tests/01-run.py
@@ -12,6 +12,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def testfunc(child):
     child.expect([r"OK \([0-9]+ tests\)",
                   r"error: unable to initialize RTC \[I2C initialization error\]"])
diff --git a/tests/driver_grove_ledbar/tests/01-run.py b/tests/driver_grove_ledbar/tests/01-run.py
index 70e38e81acb444cf2e4e9d7940d0c53ad664ed43..3d121d9933ca877f1a3de5e3909c5460273d8409 100755
--- a/tests/driver_grove_ledbar/tests/01-run.py
+++ b/tests/driver_grove_ledbar/tests/01-run.py
@@ -13,6 +13,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def testfunc(child):
     child.expect_exact(u"[SUCCESS]", timeout=60)
 
diff --git a/tests/driver_hd44780/tests/01-run.py b/tests/driver_hd44780/tests/01-run.py
index 1e1baaae75cb0b42228a3120140102e37a3a49c0..c3b9f15a90caeed8f527417bca197490a8b1160a 100644
--- a/tests/driver_hd44780/tests/01-run.py
+++ b/tests/driver_hd44780/tests/01-run.py
@@ -13,6 +13,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def testfunc(child):
     child.expect_exact("[START]")
     child.expect_exact("[SUCCESS]")
diff --git a/tests/driver_my9221/tests/01-run.py b/tests/driver_my9221/tests/01-run.py
index 5801a4475cb6dc201675d6d719433585b7bd2974..7e48651f8467a317ba683f35d7106f583489f2f8 100755
--- a/tests/driver_my9221/tests/01-run.py
+++ b/tests/driver_my9221/tests/01-run.py
@@ -13,6 +13,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def testfunc(child):
     child.expect_exact("[SUCCESS]", timeout=60)
 
diff --git a/tests/events/tests/01-run.py b/tests/events/tests/01-run.py
index eace7ab6ba8aefd72db81d43515651e6acdac8dd..2b3bd8b378d6d5d8793cb7da4966d89abce16092 100755
--- a/tests/events/tests/01-run.py
+++ b/tests/events/tests/01-run.py
@@ -13,6 +13,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def testfunc(child):
     child.expect_exact(u"[SUCCESS]")
 
diff --git a/tests/evtimer_msg/tests/01-run.py b/tests/evtimer_msg/tests/01-run.py
index fb96639f52ef0f4dfe290e35052c3aa3d5da193c..b6be878ca47b1006f9c8792dfa0c74766a58f6fe 100755
--- a/tests/evtimer_msg/tests/01-run.py
+++ b/tests/evtimer_msg/tests/01-run.py
@@ -15,6 +15,7 @@ import testrunner
 
 ACCEPTED_ERROR = 20
 
+
 def testfunc(child):
     child.expect(r"Testing generic evtimer \(start time = (\d+) ms\)")
     timer_offset = int(child.match.group(1))
diff --git a/tests/evtimer_underflow/tests/01-run.py b/tests/evtimer_underflow/tests/01-run.py
index 7b65ac4cc1ab95851b2dd7d14f5758500f5afb1e..926f6cee54c3bbd0322bb3c14cde953ded3e91bc 100755
--- a/tests/evtimer_underflow/tests/01-run.py
+++ b/tests/evtimer_underflow/tests/01-run.py
@@ -15,6 +15,7 @@ import testrunner
 
 how_many = 100
 
+
 def testfunc(child):
     for i in range(how_many):
         for j in range(8):
diff --git a/tests/float/tests/01-run.py b/tests/float/tests/01-run.py
index 07987991a5748c8dd1d2438e8bf2d8c18f904899..38339e9492136d894c3e75b2b69d829445fc72a3 100755
--- a/tests/float/tests/01-run.py
+++ b/tests/float/tests/01-run.py
@@ -12,6 +12,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def testfunc(child):
     child.expect_exact("Testing floating point arithmetics...")
     child.expect_exact("[SUCCESS]")
diff --git a/tests/gnrc_ipv6_ext/tests/01-run.py b/tests/gnrc_ipv6_ext/tests/01-run.py
index a03fe084486e4f0617dbbb08b1ec54e64101a000..1db44826b7d31bbe2b0fe8f21281812c6b591ca9 100755
--- a/tests/gnrc_ipv6_ext/tests/01-run.py
+++ b/tests/gnrc_ipv6_ext/tests/01-run.py
@@ -13,6 +13,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def testfunc(child):
     index = child.expect_exact([
         "ipv6: Received (src = fd01::1, dst = fd01::2, next header = 0, length = 42)",
diff --git a/tests/gnrc_ipv6_nib/tests/01-run.py b/tests/gnrc_ipv6_nib/tests/01-run.py
index c12bc5b8ca72fe0dddf3f2b354410e7984771947..d2ade821ec5c1382d228b5a72a0441b149221eed 100755
--- a/tests/gnrc_ipv6_nib/tests/01-run.py
+++ b/tests/gnrc_ipv6_nib/tests/01-run.py
@@ -13,6 +13,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def testfunc(child):
     child.expect(r"OK \(\d+ tests\)")
 
diff --git a/tests/gnrc_ipv6_nib_6ln/tests/01-run.py b/tests/gnrc_ipv6_nib_6ln/tests/01-run.py
index c12bc5b8ca72fe0dddf3f2b354410e7984771947..d2ade821ec5c1382d228b5a72a0441b149221eed 100755
--- a/tests/gnrc_ipv6_nib_6ln/tests/01-run.py
+++ b/tests/gnrc_ipv6_nib_6ln/tests/01-run.py
@@ -13,6 +13,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def testfunc(child):
     child.expect(r"OK \(\d+ tests\)")
 
diff --git a/tests/gnrc_ndp/tests/01-run.py b/tests/gnrc_ndp/tests/01-run.py
index decad68b6f7cfa2dc62304cacb1afdde85080614..1f1039f78bc10fd5db3d65b734cbe6234b316723 100755
--- a/tests/gnrc_ndp/tests/01-run.py
+++ b/tests/gnrc_ndp/tests/01-run.py
@@ -13,6 +13,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def testfunc(child):
     # 1st 6LoWPAN fragment
     child.expect(r"OK \(\d+ tests\)")
diff --git a/tests/gnrc_netif/tests/01-run.py b/tests/gnrc_netif/tests/01-run.py
index e1dc2d258296b8a104308db09831df245a3dec15..bdd3a01c84e09dca6bd25219b087598f8975ef8d 100755
--- a/tests/gnrc_netif/tests/01-run.py
+++ b/tests/gnrc_netif/tests/01-run.py
@@ -13,6 +13,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def testfunc(child):
     # embUnit tests
     child.expect(r"OK \(\d+ tests\)")
diff --git a/tests/gnrc_sixlowpan/tests/01-run.py b/tests/gnrc_sixlowpan/tests/01-run.py
index 832ad5e29e239edd5469a62284d01aa19b488404..a7d1842ceb8c2e4cf91a25f53b7128358bab8ad0 100755
--- a/tests/gnrc_sixlowpan/tests/01-run.py
+++ b/tests/gnrc_sixlowpan/tests/01-run.py
@@ -13,6 +13,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def testfunc(child):
     # 1st 6LoWPAN fragment
     child.expect_exact("PKTDUMP: data received:")
diff --git a/tests/gnrc_sock_ip/tests/01-run.py b/tests/gnrc_sock_ip/tests/01-run.py
index 7b866e9565b2448f9de9b61a49b53fc17a15af22..0f5eea832e2d52df754a92850472133488a74b6a 100755
--- a/tests/gnrc_sock_ip/tests/01-run.py
+++ b/tests/gnrc_sock_ip/tests/01-run.py
@@ -12,6 +12,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def testfunc(child):
     child.expect_exact(u"Calling test_sock_ip_create__EAFNOSUPPORT()")
     child.expect_exact(u"Calling test_sock_ip_create__EINVAL_addr()")
diff --git a/tests/gnrc_sock_udp/tests/01-run.py b/tests/gnrc_sock_udp/tests/01-run.py
index 1705cca707836d952e451dca36081167d622156b..f553d17c10cfade720aec11756bfdba630f4c86a 100755
--- a/tests/gnrc_sock_udp/tests/01-run.py
+++ b/tests/gnrc_sock_udp/tests/01-run.py
@@ -12,6 +12,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def testfunc(child):
     child.expect_exact(u"Calling test_sock_udp_create__EADDRINUSE()")
     child.expect_exact(u"Calling test_sock_udp_create__EAFNOSUPPORT()")
diff --git a/tests/libfixmath/do-test.py b/tests/libfixmath/do-test.py
index 70393f32c7b9b1abf11d075865ea7fd9d549929d..2577a511c69f0d268853d509364719c09852b613 100755
--- a/tests/libfixmath/do-test.py
+++ b/tests/libfixmath/do-test.py
@@ -47,6 +47,7 @@ FUNS = {
 
 ABS_ERROR_LIMIT = 0.011
 
+
 def main():
     total = 0
     errors = 0
diff --git a/tests/lwip/tests/01-run.py b/tests/lwip/tests/01-run.py
index 62c9e2a60c2f7a66f520df773421b1566d628591..788748c27565915c37e3bda75f01c90cbd02b84e 100755
--- a/tests/lwip/tests/01-run.py
+++ b/tests/lwip/tests/01-run.py
@@ -17,6 +17,7 @@ import pexpect
 
 DEFAULT_TIMEOUT = 5
 
+
 class Strategy(object):
     def __init__(self, func=None):
         if func != None:
@@ -28,11 +29,13 @@ class Strategy(object):
     def execute(self, *args, **kwargs):
         raise NotImplementedError()
 
+
 class ApplicationStrategy(Strategy):
     def __init__(self, app_dir=os.getcwd(), func=None):
         super(ApplicationStrategy, self).__init__(func)
         self.app_dir = app_dir
 
+
 class BoardStrategy(Strategy):
     def __init__(self, board, func=None):
         super(BoardStrategy, self).__init__(func)
@@ -50,22 +53,27 @@ class BoardStrategy(Strategy):
     def execute(self, application):
         super(BoardStrategy, self).execute(application)
 
+
 class CleanStrategy(BoardStrategy):
     def execute(self, application, env=None):
         super(CleanStrategy, self).__run_make(application, ("-B", "clean"), env)
 
+
 class BuildStrategy(BoardStrategy):
     def execute(self, application, env=None):
         super(BuildStrategy, self).__run_make(application, ("all",), env)
 
+
 class FlashStrategy(BoardStrategy):
     def execute(self, application, env=None):
         super(FlashStrategy, self).__run_make(application, ("all",), env)
 
+
 class ResetStrategy(BoardStrategy):
     def execute(self, application, env=None):
         super(ResetStrategy, self).__run_make(application, ("reset",), env)
 
+
 class Board(object):
     def __init__(self, name, port=None, serial=None, clean=None,
                  build=None, flash=None,
@@ -119,6 +127,7 @@ class Board(object):
     def reset(self, application=os.getcwd(), env=None):
         self.reset_strategy.execute(application, env)
 
+
 class BoardGroup(object):
     def __init__(self, boards):
         self.boards = boards
@@ -148,6 +157,7 @@ class BoardGroup(object):
         for board in self.boards:
             board.reset(application, env)
 
+
 def default_test_case(board_group, application, env=None):
     for board in board_group:
         env = os.environ.copy()
@@ -159,6 +169,7 @@ def default_test_case(board_group, application, env=None):
                            logfile=sys.stdout) as spawn:
             spawn.expect("TEST: SUCCESS")
 
+
 class TestStrategy(ApplicationStrategy):
     def execute(self, board_groups, test_cases=[default_test_case],
                 timeout=DEFAULT_TIMEOUT, env=None):
@@ -171,11 +182,13 @@ class TestStrategy(ApplicationStrategy):
                 sys.stdout.flush()
             print()
 
+
 def get_ipv6_address(spawn):
     spawn.sendline(u"ifconfig")
     spawn.expect(u"[A-Za-z0-9]{2}_[0-9]+:  inet6 (fe80::[0-9a-f:]+)")
     return spawn.match.group(1)
 
+
 def test_ipv6_send(board_group, application, env=None):
     env_sender = os.environ.copy()
     if env != None:
@@ -199,6 +212,7 @@ def test_ipv6_send(board_group, application, env=None):
                             (receiver_ip, ipprot))
         receiver.expect(u"00000000  01  23  45  67  89  AB  CD  EF")
 
+
 def test_udpv6_send(board_group, application, env=None):
     env_sender = os.environ.copy()
     if env != None:
@@ -223,6 +237,7 @@ def test_udpv6_send(board_group, application, env=None):
                             (receiver_ip, port))
         receiver.expect(u"00000000  AB  CD  EF")
 
+
 def test_tcpv6_send(board_group, application, env=None):
     env_client = os.environ.copy()
     if env != None:
@@ -252,6 +267,7 @@ def test_tcpv6_send(board_group, application, env=None):
         client.sendline(u"tcp send affe:abe")
         client.expect_exact(u"could not send")
 
+
 def test_triple_send(board_group, application, env=None):
     env_sender = os.environ.copy()
     if env != None:
diff --git a/tests/lwip_sock_ip/tests/01-run.py b/tests/lwip_sock_ip/tests/01-run.py
index f466335371d491049a6b09315c0f7e0df32c32ad..96f73bdd80b20c9974bbe85625c27c1d5672c964 100755
--- a/tests/lwip_sock_ip/tests/01-run.py
+++ b/tests/lwip_sock_ip/tests/01-run.py
@@ -12,12 +12,15 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def _ipv6_tests(code):
     return code & (1 << 6)
 
+
 def _ipv4_tests(code):
     return code & (1 << 4)
 
+
 def testfunc(child):
     child.expect(u"code (0x[0-9a-f]{2})")
     code = int(child.match.group(1), base=16)
diff --git a/tests/lwip_sock_tcp/tests/01-run.py b/tests/lwip_sock_tcp/tests/01-run.py
index 7a98ab975a5c9f508802f7e8cd2a5aed8c37418b..176c9985228c2726eb771d524a197f55c320b7dd 100755
--- a/tests/lwip_sock_tcp/tests/01-run.py
+++ b/tests/lwip_sock_tcp/tests/01-run.py
@@ -12,15 +12,19 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def _reuse_tests(code):
     return code & 1
 
+
 def _ipv6_tests(code):
     return code & (1 << 6)
 
+
 def _ipv4_tests(code):
     return code & (1 << 4)
 
+
 def testfunc(child):
     child.expect(u"code (0x[0-9a-f]{2})")
     code = int(child.match.group(1), base=16)
diff --git a/tests/lwip_sock_udp/tests/01-run.py b/tests/lwip_sock_udp/tests/01-run.py
index 0a9e036727d25f8f3395276b9b2c67afeee292c1..ba0887ad2cc3aac53cc71121d8b6e3449e5d61e1 100755
--- a/tests/lwip_sock_udp/tests/01-run.py
+++ b/tests/lwip_sock_udp/tests/01-run.py
@@ -12,15 +12,19 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def _reuse_tests(code):
     return code & 1
 
+
 def _ipv6_tests(code):
     return code & (1 << 6)
 
+
 def _ipv4_tests(code):
     return code & (1 << 4)
 
+
 def testfunc(child):
     child.expect(u"code (0x[0-9a-f]{2})")
     code = int(child.match.group(1), base=16)
diff --git a/tests/msg_avail/tests/01-run.py b/tests/msg_avail/tests/01-run.py
index eace7ab6ba8aefd72db81d43515651e6acdac8dd..2b3bd8b378d6d5d8793cb7da4966d89abce16092 100755
--- a/tests/msg_avail/tests/01-run.py
+++ b/tests/msg_avail/tests/01-run.py
@@ -13,6 +13,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def testfunc(child):
     child.expect_exact(u"[SUCCESS]")
 
diff --git a/tests/msg_send_receive/tests/01-run.py b/tests/msg_send_receive/tests/01-run.py
index 3e25a1bc50c401a9ef3f984c20adc7c622ff6db0..9ff95cf953a44984edb9f0ae8531fcfc8da2ad4a 100755
--- a/tests/msg_send_receive/tests/01-run.py
+++ b/tests/msg_send_receive/tests/01-run.py
@@ -12,6 +12,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def testfunc(child):
     child.expect(u"Test successful.")
 
diff --git a/tests/mutex_order/tests/01-run.py b/tests/mutex_order/tests/01-run.py
index 7448a66b468acf6f3d729799df601ba2727511c0..85e800f9486933f58236a8f14e7aee1f59bdb2e4 100755
--- a/tests/mutex_order/tests/01-run.py
+++ b/tests/mutex_order/tests/01-run.py
@@ -21,6 +21,7 @@ thread_prio = {
         7:  1
         }
 
+
 def testfunc(child):
     for k in thread_prio.keys():
         child.expect(u"T%i \(prio %i\): trying to lock mutex now" % (k, thread_prio[k]))
diff --git a/tests/od/tests/01-run.py b/tests/od/tests/01-run.py
index b9808e85bd0607d3ba092420627bdc9ce1cd24b5..cb4e8f7f625ede12fbb872a062cc95f00d0d3e64 100755
--- a/tests/od/tests/01-run.py
+++ b/tests/od/tests/01-run.py
@@ -12,6 +12,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def testfunc(child):
     child.expect_exact("od_hex_dump(short_str, sizeof(short_str), OD_WIDTH_DEFAULT)")
     child.expect_exact("00000000  41  42  00")
diff --git a/tests/od/tests/02-run.py b/tests/od/tests/02-run.py
index 0e2e6bef51ba95e4f2aad7b31787577257d8fffe..5d6c14abe8c26cf5a5bc9c3dcf17f75f38f14452 100755
--- a/tests/od/tests/02-run.py
+++ b/tests/od/tests/02-run.py
@@ -12,6 +12,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def testfunc(child):
     child.expect_exact("od_hex_dump(short_str, sizeof(short_str), OD_WIDTH_DEFAULT)")
     child.expect_exact("00000000  41  42  00                                                      AB.")
diff --git a/tests/pkg_tiny-asn1/tests/01-run.py b/tests/pkg_tiny-asn1/tests/01-run.py
index 259eaf62642d229e779ebb8cbe7e4bec1739154b..0c25de935437d7d47903e1c79ce476c540146244 100755
--- a/tests/pkg_tiny-asn1/tests/01-run.py
+++ b/tests/pkg_tiny-asn1/tests/01-run.py
@@ -13,6 +13,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def testfunc(child):
     child.expect('Decoding finished succesfully')
 
diff --git a/tests/pkg_umorse/tests/01-run.py b/tests/pkg_umorse/tests/01-run.py
index 6dcb50421064c79ee9f644251e1f51d9f1b9f2cb..19c6dd918f06c9ad19e22dda9b6628dd25b55512 100755
--- a/tests/pkg_umorse/tests/01-run.py
+++ b/tests/pkg_umorse/tests/01-run.py
@@ -12,8 +12,8 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
-def testfunc(child):
 
+def testfunc(child):
     child.expect(u".... . ._.. ._.. ___ / ._. .. ___ _ ___ ...", timeout=30)
     child.expect(u"_ .... .. ... / .. ... / .._ __ ___ ._. ... .", timeout=30)
 
diff --git a/tests/posix_semaphore/tests/01-run.py b/tests/posix_semaphore/tests/01-run.py
index e9c61de8fbe6c2dc52c5d9151f0a1ddc9ccbd056..6e827717ba2e402acf2a16d375c187db1b383001 100755
--- a/tests/posix_semaphore/tests/01-run.py
+++ b/tests/posix_semaphore/tests/01-run.py
@@ -12,6 +12,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def test1(term):
     term.expect_exact("######################### TEST1:")
     term.expect_exact("first: sem_init")
@@ -34,6 +35,7 @@ def test1(term):
     term.expect_exact("first: sem_destroy")
     term.expect_exact("first: end")
 
+
 def test2(term):
     term.expect_exact("######################### TEST2:")
     term.expect_exact("first: sem_init")
@@ -64,6 +66,7 @@ def test2(term):
     term.expect_exact("Thread 'priority 5' woke up.")
     term.expect_exact("Back in main thread.")
 
+
 def test3(term):
     term.expect_exact("######################### TEST3:")
     term.expect_exact("first: sem_init s1")
@@ -80,6 +83,7 @@ def test3(term):
     term.expect_exact("post s1")
     term.expect_exact("Thread 2 woke up after waiting for s1.")
 
+
 def test4(term):
     term.expect_exact("######################### TEST4:")
     term.expect_exact("first: sem_init s1")
@@ -87,6 +91,7 @@ def test4(term):
     term.expect_exact("first: timed out")
     term.expect(r"first: waited 1\d{6} usec")
 
+
 def testfunc(child):
     test1(child)
     test2(child)
diff --git a/tests/posix_time/tests/01-run.py b/tests/posix_time/tests/01-run.py
index 285e4d807e97d764b5eb5a89b228be9f7cdfcacc..8e2f66173a5e9eaab561605ed29b659a243d3b8b 100755
--- a/tests/posix_time/tests/01-run.py
+++ b/tests/posix_time/tests/01-run.py
@@ -18,9 +18,11 @@ import testrunner
 US_PER_SEC = 1000000
 EXTERNAL_JITTER = 0.15
 
+
 class InvalidTimeout(Exception):
     pass
 
+
 def testfunc(child):
     try:
         child.expect_exact("Please hit any key and then ENTER to continue")
diff --git a/tests/ps_schedstatistics/tests/01-run.py b/tests/ps_schedstatistics/tests/01-run.py
index 4a0227fc8abce574968d4b5134c058a9167801bc..3138b3dd091c8a75326aab2ff29f1769a22a907e 100755
--- a/tests/ps_schedstatistics/tests/01-run.py
+++ b/tests/ps_schedstatistics/tests/01-run.py
@@ -35,6 +35,7 @@ PS_EXPECTED = (
     ('\t    | SUM                  |            |     | \d+  (\d+)')
 )
 
+
 def _check_startup(child):
     for i in range(5):
         child.expect_exact('Creating thread #{}, next={}'
diff --git a/tests/rmutex/tests/01-run.py b/tests/rmutex/tests/01-run.py
index 174b6e779c6ddb1168685e765740a3edadc62448..f9a86d1c60ac986cf5fe49475db7781be9658d01 100755
--- a/tests/rmutex/tests/01-run.py
+++ b/tests/rmutex/tests/01-run.py
@@ -30,9 +30,11 @@ lock_depth = {
         7:  5
         }
 
+
 def thread_prio_sort(x):
     return thread_prio.get(x)*1000 + x
 
+
 def testfunc(child):
     for k in thread_prio.keys():
         child.expect(u"T%i \(prio %i, depth 0\): trying to lock rmutex now" %
diff --git a/tests/thread_cooperation/tests/01-run.py b/tests/thread_cooperation/tests/01-run.py
index 48764182311b8fd30a8413b2e9d7c5fdcbd2f6a7..9b6ecbfbd15e609c5eaf25d4f74b6e3f28a4791c 100755
--- a/tests/thread_cooperation/tests/01-run.py
+++ b/tests/thread_cooperation/tests/01-run.py
@@ -13,6 +13,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def testfunc(child):
     child.expect(r"MAIN: reply from T-\d+")
     child.expect(r"MAIN: \d+! = \d+")
diff --git a/tests/thread_msg_block_w_queue/tests/01-run.py b/tests/thread_msg_block_w_queue/tests/01-run.py
index 69f13d11d46dd889ada039a06979c5413e9c5ef5..0a9a8ee4bdf8e1acf8cf512c794b1a3d16ad217b 100755
--- a/tests/thread_msg_block_w_queue/tests/01-run.py
+++ b/tests/thread_msg_block_w_queue/tests/01-run.py
@@ -12,6 +12,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def testfunc(child):
     child.expect('sender_thread start\r\n')
     child.expect('main thread alive\r\n')
diff --git a/tests/thread_msg_block_wo_queue/tests/01-run.py b/tests/thread_msg_block_wo_queue/tests/01-run.py
index 69f13d11d46dd889ada039a06979c5413e9c5ef5..0a9a8ee4bdf8e1acf8cf512c794b1a3d16ad217b 100755
--- a/tests/thread_msg_block_wo_queue/tests/01-run.py
+++ b/tests/thread_msg_block_wo_queue/tests/01-run.py
@@ -12,6 +12,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def testfunc(child):
     child.expect('sender_thread start\r\n')
     child.expect('main thread alive\r\n')
diff --git a/tests/trickle/tests/01-run.py b/tests/trickle/tests/01-run.py
index ed0d8aa28e90810291df8c5ad93bfbefce5bb301..33ad94d77292eeb27cdb8f3704fa2f0ceb4a0d84 100755
--- a/tests/trickle/tests/01-run.py
+++ b/tests/trickle/tests/01-run.py
@@ -12,6 +12,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def testfunc(child):
     child.expect_exact("[START]")
 
diff --git a/tests/unittests/tests/01-run.py b/tests/unittests/tests/01-run.py
index 8764fc08e29af60fb0cb80a82b48d7f8a691ac75..c8183c2a4feadf66cec10582deeddaae14398013 100755
--- a/tests/unittests/tests/01-run.py
+++ b/tests/unittests/tests/01-run.py
@@ -12,6 +12,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def testfunc(child):
     child.expect(u"OK \\([0-9]+ tests\\)")
 
diff --git a/tests/xtimer_hang/tests/01-run.py b/tests/xtimer_hang/tests/01-run.py
index 9e58b4e9456fc9aec70a0971da634d56c6cdf7b0..cc44b205af5461739930b7a4ea3b8aeaccd3da78 100755
--- a/tests/xtimer_hang/tests/01-run.py
+++ b/tests/xtimer_hang/tests/01-run.py
@@ -12,6 +12,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def testfunc(child):
     child.expect_exact("[START]")
 
diff --git a/tests/xtimer_msg_receive_timeout/tests/01-run.py b/tests/xtimer_msg_receive_timeout/tests/01-run.py
index 37ac3704d866d3ec72d484886470a3ceb80864e7..5cfc83c7a58332346c39910f1ebedd639c7b77a2 100755
--- a/tests/xtimer_msg_receive_timeout/tests/01-run.py
+++ b/tests/xtimer_msg_receive_timeout/tests/01-run.py
@@ -12,6 +12,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def testfunc(child):
     child.expect("[START]")
     for i in range(5):
diff --git a/tests/xtimer_now64_continuity/tests/01-run.py b/tests/xtimer_now64_continuity/tests/01-run.py
index a81d8efba9983676e9f2ffe1b3cda93b4c54126c..828efb660643b9a00328bde02eef4b01e17337e9 100755
--- a/tests/xtimer_now64_continuity/tests/01-run.py
+++ b/tests/xtimer_now64_continuity/tests/01-run.py
@@ -12,6 +12,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def testfunc(child):
     child.expect_exact("[START]")
     child.expect(u"\[RESULTS\] min=\d+, avg=\d+, max=\d+")
diff --git a/tests/xtimer_periodic_wakeup/tests/01-run.py b/tests/xtimer_periodic_wakeup/tests/01-run.py
index f9fc611b87fa6d3c0d854f78795b998771455df2..433ce162413ee7cdbdbc5a096c9624a9d68c0e1a 100755
--- a/tests/xtimer_periodic_wakeup/tests/01-run.py
+++ b/tests/xtimer_periodic_wakeup/tests/01-run.py
@@ -12,6 +12,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def testfunc(child):
     child.expect_exact("xtimer_periodic_wakeup test application.")
 
diff --git a/tests/xtimer_remove/tests/01-run.py b/tests/xtimer_remove/tests/01-run.py
index 203ad6dd8cfceabe6a2f7b2cdbf3413497cb97fe..8b7c52706641c121a93e7e36897de627c4fedc94 100755
--- a/tests/xtimer_remove/tests/01-run.py
+++ b/tests/xtimer_remove/tests/01-run.py
@@ -12,6 +12,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def testfunc(child):
     child.expect_exact("xtimer_remove test application.")
     child.expect_exact("Setting 3 timers, removing timer 0/3")
diff --git a/tests/xtimer_reset/tests/01-run.py b/tests/xtimer_reset/tests/01-run.py
index 92cc933adbacba4d0c0544cf44f1bd305bf23df9..87f31a0b89fa03dbe00c3ef308610b471bc89e7d 100755
--- a/tests/xtimer_reset/tests/01-run.py
+++ b/tests/xtimer_reset/tests/01-run.py
@@ -12,6 +12,7 @@ import sys
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
+
 def testfunc(child):
     child.expect_exact("This test tests re-setting of an already active timer.")
     child.expect_exact("It should print three times \"now=<value>\", with "
diff --git a/tests/xtimer_usleep/tests/01-run.py b/tests/xtimer_usleep/tests/01-run.py
index 1d8cb6ecfb6393ea404ad43a329751d180f354d5..489cae3b91c1fb48d9b8b14a5987463c7dadde88 100755
--- a/tests/xtimer_usleep/tests/01-run.py
+++ b/tests/xtimer_usleep/tests/01-run.py
@@ -20,9 +20,11 @@ US_PER_SEC = 1000000
 INTERNAL_JITTER = 0.05
 EXTERNAL_JITTER = 0.15
 
+
 class InvalidTimeout(Exception):
     pass
 
+
 def testfunc(child):
     child.expect(u"Running test (\\d+) times with (\\d+) distinct sleep times")
     RUNS = int(child.match.group(1))
diff --git a/tests/xtimer_usleep_short/tests/01-run.py b/tests/xtimer_usleep_short/tests/01-run.py
index 3379c94e4835239d8f7459be74ac1637fc7a0884..5fc2385ef527e1642d8925280a58f276e269eb0b 100755
--- a/tests/xtimer_usleep_short/tests/01-run.py
+++ b/tests/xtimer_usleep_short/tests/01-run.py
@@ -13,8 +13,8 @@ import pexpect
 sys.path.append(os.path.join(os.environ['RIOTBASE'], 'dist/tools/testrunner'))
 import testrunner
 
-def testfunc(child):
 
+def testfunc(child):
     child.expect(u"This test will call xtimer_usleep for values from \\d+ down to \\d+\r\n")
 
     i = 500