Whitespace normalization.
diff --git a/Lib/doctest.py b/Lib/doctest.py
index ff068a1..9cc7fed 100644
--- a/Lib/doctest.py
+++ b/Lib/doctest.py
@@ -1601,7 +1601,7 @@
 
     def __str__(self):
         return str(self.test)
-    
+
 class DebugRunner(DocTestRunner):
     r"""Run doc tests but raise an exception as soon as there is a failure.
 
@@ -1673,7 +1673,7 @@
          Traceback (most recent call last):
          ...
          UnexpectedException: <DocTest foo from foo.py:0 (2 examples)>
-         
+
          >>> del test.globs['__builtins__']
          >>> test.globs
          {'x': 2}
diff --git a/Lib/encodings/iso8859_11.py b/Lib/encodings/iso8859_11.py
index ab242af..dfe46b1 100644
--- a/Lib/encodings/iso8859_11.py
+++ b/Lib/encodings/iso8859_11.py
@@ -35,101 +35,101 @@
 
 decoding_map = codecs.make_identity_dict(range(256))
 decoding_map.update({
-	0x00a1: 0x0e01,	# 	THAI CHARACTER KO KAI
-	0x00a2: 0x0e02,	# 	THAI CHARACTER KHO KHAI
-	0x00a3: 0x0e03,	# 	THAI CHARACTER KHO KHUAT
-	0x00a4: 0x0e04,	# 	THAI CHARACTER KHO KHWAI
-	0x00a5: 0x0e05,	# 	THAI CHARACTER KHO KHON
-	0x00a6: 0x0e06,	# 	THAI CHARACTER KHO RAKHANG
-	0x00a7: 0x0e07,	# 	THAI CHARACTER NGO NGU
-	0x00a8: 0x0e08,	# 	THAI CHARACTER CHO CHAN
-	0x00a9: 0x0e09,	# 	THAI CHARACTER CHO CHING
-	0x00aa: 0x0e0a,	# 	THAI CHARACTER CHO CHANG
-	0x00ab: 0x0e0b,	# 	THAI CHARACTER SO SO
-	0x00ac: 0x0e0c,	# 	THAI CHARACTER CHO CHOE
-	0x00ad: 0x0e0d,	# 	THAI CHARACTER YO YING
-	0x00ae: 0x0e0e,	# 	THAI CHARACTER DO CHADA
-	0x00af: 0x0e0f,	# 	THAI CHARACTER TO PATAK
-	0x00b0: 0x0e10,	# 	THAI CHARACTER THO THAN
-	0x00b1: 0x0e11,	# 	THAI CHARACTER THO NANGMONTHO
-	0x00b2: 0x0e12,	# 	THAI CHARACTER THO PHUTHAO
-	0x00b3: 0x0e13,	# 	THAI CHARACTER NO NEN
-	0x00b4: 0x0e14,	# 	THAI CHARACTER DO DEK
-	0x00b5: 0x0e15,	# 	THAI CHARACTER TO TAO
-	0x00b6: 0x0e16,	# 	THAI CHARACTER THO THUNG
-	0x00b7: 0x0e17,	# 	THAI CHARACTER THO THAHAN
-	0x00b8: 0x0e18,	# 	THAI CHARACTER THO THONG
-	0x00b9: 0x0e19,	# 	THAI CHARACTER NO NU
-	0x00ba: 0x0e1a,	# 	THAI CHARACTER BO BAIMAI
-	0x00bb: 0x0e1b,	# 	THAI CHARACTER PO PLA
-	0x00bc: 0x0e1c,	# 	THAI CHARACTER PHO PHUNG
-	0x00bd: 0x0e1d,	# 	THAI CHARACTER FO FA
-	0x00be: 0x0e1e,	# 	THAI CHARACTER PHO PHAN
-	0x00bf: 0x0e1f,	# 	THAI CHARACTER FO FAN
-	0x00c0: 0x0e20,	# 	THAI CHARACTER PHO SAMPHAO
-	0x00c1: 0x0e21,	# 	THAI CHARACTER MO MA
-	0x00c2: 0x0e22,	# 	THAI CHARACTER YO YAK
-	0x00c3: 0x0e23,	# 	THAI CHARACTER RO RUA
-	0x00c4: 0x0e24,	# 	THAI CHARACTER RU
-	0x00c5: 0x0e25,	# 	THAI CHARACTER LO LING
-	0x00c6: 0x0e26,	# 	THAI CHARACTER LU
-	0x00c7: 0x0e27,	# 	THAI CHARACTER WO WAEN
-	0x00c8: 0x0e28,	# 	THAI CHARACTER SO SALA
-	0x00c9: 0x0e29,	# 	THAI CHARACTER SO RUSI
-	0x00ca: 0x0e2a,	# 	THAI CHARACTER SO SUA
-	0x00cb: 0x0e2b,	# 	THAI CHARACTER HO HIP
-	0x00cc: 0x0e2c,	# 	THAI CHARACTER LO CHULA
-	0x00cd: 0x0e2d,	# 	THAI CHARACTER O ANG
-	0x00ce: 0x0e2e,	# 	THAI CHARACTER HO NOKHUK
-	0x00cf: 0x0e2f,	# 	THAI CHARACTER PAIYANNOI
-	0x00d0: 0x0e30,	# 	THAI CHARACTER SARA A
-	0x00d1: 0x0e31,	# 	THAI CHARACTER MAI HAN-AKAT
-	0x00d2: 0x0e32,	# 	THAI CHARACTER SARA AA
-	0x00d3: 0x0e33,	# 	THAI CHARACTER SARA AM
-	0x00d4: 0x0e34,	# 	THAI CHARACTER SARA I
-	0x00d5: 0x0e35,	# 	THAI CHARACTER SARA II
-	0x00d6: 0x0e36,	# 	THAI CHARACTER SARA UE
-	0x00d7: 0x0e37,	# 	THAI CHARACTER SARA UEE
-	0x00d8: 0x0e38,	# 	THAI CHARACTER SARA U
-	0x00d9: 0x0e39,	# 	THAI CHARACTER SARA UU
-	0x00da: 0x0e3a,	# 	THAI CHARACTER PHINTHU
-	0x00db: None,
-	0x00dc: None,
-	0x00dd: None,
-	0x00de: None,
-	0x00df: 0x0e3f,	# 	THAI CURRENCY SYMBOL BAHT
-	0x00e0: 0x0e40,	# 	THAI CHARACTER SARA E
-	0x00e1: 0x0e41,	# 	THAI CHARACTER SARA AE
-	0x00e2: 0x0e42,	# 	THAI CHARACTER SARA O
-	0x00e3: 0x0e43,	# 	THAI CHARACTER SARA AI MAIMUAN
-	0x00e4: 0x0e44,	# 	THAI CHARACTER SARA AI MAIMALAI
-	0x00e5: 0x0e45,	# 	THAI CHARACTER LAKKHANGYAO
-	0x00e6: 0x0e46,	# 	THAI CHARACTER MAIYAMOK
-	0x00e7: 0x0e47,	# 	THAI CHARACTER MAITAIKHU
-	0x00e8: 0x0e48,	# 	THAI CHARACTER MAI EK
-	0x00e9: 0x0e49,	# 	THAI CHARACTER MAI THO
-	0x00ea: 0x0e4a,	# 	THAI CHARACTER MAI TRI
-	0x00eb: 0x0e4b,	# 	THAI CHARACTER MAI CHATTAWA
-	0x00ec: 0x0e4c,	# 	THAI CHARACTER THANTHAKHAT
-	0x00ed: 0x0e4d,	# 	THAI CHARACTER NIKHAHIT
-	0x00ee: 0x0e4e,	# 	THAI CHARACTER YAMAKKAN
-	0x00ef: 0x0e4f,	# 	THAI CHARACTER FONGMAN
-	0x00f0: 0x0e50,	# 	THAI DIGIT ZERO
-	0x00f1: 0x0e51,	# 	THAI DIGIT ONE
-	0x00f2: 0x0e52,	# 	THAI DIGIT TWO
-	0x00f3: 0x0e53,	# 	THAI DIGIT THREE
-	0x00f4: 0x0e54,	# 	THAI DIGIT FOUR
-	0x00f5: 0x0e55,	# 	THAI DIGIT FIVE
-	0x00f6: 0x0e56,	# 	THAI DIGIT SIX
-	0x00f7: 0x0e57,	# 	THAI DIGIT SEVEN
-	0x00f8: 0x0e58,	# 	THAI DIGIT EIGHT
-	0x00f9: 0x0e59,	# 	THAI DIGIT NINE
-	0x00fa: 0x0e5a,	# 	THAI CHARACTER ANGKHANKHU
-	0x00fb: 0x0e5b,	# 	THAI CHARACTER KHOMUT
-	0x00fc: None,
-	0x00fd: None,
-	0x00fe: None,
-	0x00ff: None,
+        0x00a1: 0x0e01, #       THAI CHARACTER KO KAI
+        0x00a2: 0x0e02, #       THAI CHARACTER KHO KHAI
+        0x00a3: 0x0e03, #       THAI CHARACTER KHO KHUAT
+        0x00a4: 0x0e04, #       THAI CHARACTER KHO KHWAI
+        0x00a5: 0x0e05, #       THAI CHARACTER KHO KHON
+        0x00a6: 0x0e06, #       THAI CHARACTER KHO RAKHANG
+        0x00a7: 0x0e07, #       THAI CHARACTER NGO NGU
+        0x00a8: 0x0e08, #       THAI CHARACTER CHO CHAN
+        0x00a9: 0x0e09, #       THAI CHARACTER CHO CHING
+        0x00aa: 0x0e0a, #       THAI CHARACTER CHO CHANG
+        0x00ab: 0x0e0b, #       THAI CHARACTER SO SO
+        0x00ac: 0x0e0c, #       THAI CHARACTER CHO CHOE
+        0x00ad: 0x0e0d, #       THAI CHARACTER YO YING
+        0x00ae: 0x0e0e, #       THAI CHARACTER DO CHADA
+        0x00af: 0x0e0f, #       THAI CHARACTER TO PATAK
+        0x00b0: 0x0e10, #       THAI CHARACTER THO THAN
+        0x00b1: 0x0e11, #       THAI CHARACTER THO NANGMONTHO
+        0x00b2: 0x0e12, #       THAI CHARACTER THO PHUTHAO
+        0x00b3: 0x0e13, #       THAI CHARACTER NO NEN
+        0x00b4: 0x0e14, #       THAI CHARACTER DO DEK
+        0x00b5: 0x0e15, #       THAI CHARACTER TO TAO
+        0x00b6: 0x0e16, #       THAI CHARACTER THO THUNG
+        0x00b7: 0x0e17, #       THAI CHARACTER THO THAHAN
+        0x00b8: 0x0e18, #       THAI CHARACTER THO THONG
+        0x00b9: 0x0e19, #       THAI CHARACTER NO NU
+        0x00ba: 0x0e1a, #       THAI CHARACTER BO BAIMAI
+        0x00bb: 0x0e1b, #       THAI CHARACTER PO PLA
+        0x00bc: 0x0e1c, #       THAI CHARACTER PHO PHUNG
+        0x00bd: 0x0e1d, #       THAI CHARACTER FO FA
+        0x00be: 0x0e1e, #       THAI CHARACTER PHO PHAN
+        0x00bf: 0x0e1f, #       THAI CHARACTER FO FAN
+        0x00c0: 0x0e20, #       THAI CHARACTER PHO SAMPHAO
+        0x00c1: 0x0e21, #       THAI CHARACTER MO MA
+        0x00c2: 0x0e22, #       THAI CHARACTER YO YAK
+        0x00c3: 0x0e23, #       THAI CHARACTER RO RUA
+        0x00c4: 0x0e24, #       THAI CHARACTER RU
+        0x00c5: 0x0e25, #       THAI CHARACTER LO LING
+        0x00c6: 0x0e26, #       THAI CHARACTER LU
+        0x00c7: 0x0e27, #       THAI CHARACTER WO WAEN
+        0x00c8: 0x0e28, #       THAI CHARACTER SO SALA
+        0x00c9: 0x0e29, #       THAI CHARACTER SO RUSI
+        0x00ca: 0x0e2a, #       THAI CHARACTER SO SUA
+        0x00cb: 0x0e2b, #       THAI CHARACTER HO HIP
+        0x00cc: 0x0e2c, #       THAI CHARACTER LO CHULA
+        0x00cd: 0x0e2d, #       THAI CHARACTER O ANG
+        0x00ce: 0x0e2e, #       THAI CHARACTER HO NOKHUK
+        0x00cf: 0x0e2f, #       THAI CHARACTER PAIYANNOI
+        0x00d0: 0x0e30, #       THAI CHARACTER SARA A
+        0x00d1: 0x0e31, #       THAI CHARACTER MAI HAN-AKAT
+        0x00d2: 0x0e32, #       THAI CHARACTER SARA AA
+        0x00d3: 0x0e33, #       THAI CHARACTER SARA AM
+        0x00d4: 0x0e34, #       THAI CHARACTER SARA I
+        0x00d5: 0x0e35, #       THAI CHARACTER SARA II
+        0x00d6: 0x0e36, #       THAI CHARACTER SARA UE
+        0x00d7: 0x0e37, #       THAI CHARACTER SARA UEE
+        0x00d8: 0x0e38, #       THAI CHARACTER SARA U
+        0x00d9: 0x0e39, #       THAI CHARACTER SARA UU
+        0x00da: 0x0e3a, #       THAI CHARACTER PHINTHU
+        0x00db: None,
+        0x00dc: None,
+        0x00dd: None,
+        0x00de: None,
+        0x00df: 0x0e3f, #       THAI CURRENCY SYMBOL BAHT
+        0x00e0: 0x0e40, #       THAI CHARACTER SARA E
+        0x00e1: 0x0e41, #       THAI CHARACTER SARA AE
+        0x00e2: 0x0e42, #       THAI CHARACTER SARA O
+        0x00e3: 0x0e43, #       THAI CHARACTER SARA AI MAIMUAN
+        0x00e4: 0x0e44, #       THAI CHARACTER SARA AI MAIMALAI
+        0x00e5: 0x0e45, #       THAI CHARACTER LAKKHANGYAO
+        0x00e6: 0x0e46, #       THAI CHARACTER MAIYAMOK
+        0x00e7: 0x0e47, #       THAI CHARACTER MAITAIKHU
+        0x00e8: 0x0e48, #       THAI CHARACTER MAI EK
+        0x00e9: 0x0e49, #       THAI CHARACTER MAI THO
+        0x00ea: 0x0e4a, #       THAI CHARACTER MAI TRI
+        0x00eb: 0x0e4b, #       THAI CHARACTER MAI CHATTAWA
+        0x00ec: 0x0e4c, #       THAI CHARACTER THANTHAKHAT
+        0x00ed: 0x0e4d, #       THAI CHARACTER NIKHAHIT
+        0x00ee: 0x0e4e, #       THAI CHARACTER YAMAKKAN
+        0x00ef: 0x0e4f, #       THAI CHARACTER FONGMAN
+        0x00f0: 0x0e50, #       THAI DIGIT ZERO
+        0x00f1: 0x0e51, #       THAI DIGIT ONE
+        0x00f2: 0x0e52, #       THAI DIGIT TWO
+        0x00f3: 0x0e53, #       THAI DIGIT THREE
+        0x00f4: 0x0e54, #       THAI DIGIT FOUR
+        0x00f5: 0x0e55, #       THAI DIGIT FIVE
+        0x00f6: 0x0e56, #       THAI DIGIT SIX
+        0x00f7: 0x0e57, #       THAI DIGIT SEVEN
+        0x00f8: 0x0e58, #       THAI DIGIT EIGHT
+        0x00f9: 0x0e59, #       THAI DIGIT NINE
+        0x00fa: 0x0e5a, #       THAI CHARACTER ANGKHANKHU
+        0x00fb: 0x0e5b, #       THAI CHARACTER KHOMUT
+        0x00fc: None,
+        0x00fd: None,
+        0x00fe: None,
+        0x00ff: None,
 })
 
 ### Encoding Map
diff --git a/Lib/encodings/iso8859_16.py b/Lib/encodings/iso8859_16.py
index cfd61f3..80c0740 100644
--- a/Lib/encodings/iso8859_16.py
+++ b/Lib/encodings/iso8859_16.py
@@ -35,46 +35,46 @@
 
 decoding_map = codecs.make_identity_dict(range(256))
 decoding_map.update({
-	0x00a1: 0x0104,	# 	LATIN CAPITAL LETTER A WITH OGONEK
-	0x00a2: 0x0105,	# 	LATIN SMALL LETTER A WITH OGONEK
-	0x00a3: 0x0141,	# 	LATIN CAPITAL LETTER L WITH STROKE
-	0x00a4: 0x20ac,	# 	EURO SIGN
-	0x00a5: 0x201e,	# 	DOUBLE LOW-9 QUOTATION MARK
-	0x00a6: 0x0160,	# 	LATIN CAPITAL LETTER S WITH CARON
-	0x00a8: 0x0161,	# 	LATIN SMALL LETTER S WITH CARON
-	0x00aa: 0x0218,	# 	LATIN CAPITAL LETTER S WITH COMMA BELOW
-	0x00ac: 0x0179,	# 	LATIN CAPITAL LETTER Z WITH ACUTE
-	0x00ae: 0x017a,	# 	LATIN SMALL LETTER Z WITH ACUTE
-	0x00af: 0x017b,	# 	LATIN CAPITAL LETTER Z WITH DOT ABOVE
-	0x00b2: 0x010c,	# 	LATIN CAPITAL LETTER C WITH CARON
-	0x00b3: 0x0142,	# 	LATIN SMALL LETTER L WITH STROKE
-	0x00b4: 0x017d,	# 	LATIN CAPITAL LETTER Z WITH CARON
-	0x00b5: 0x201d,	# 	RIGHT DOUBLE QUOTATION MARK
-	0x00b8: 0x017e,	# 	LATIN SMALL LETTER Z WITH CARON
-	0x00b9: 0x010d,	# 	LATIN SMALL LETTER C WITH CARON
-	0x00ba: 0x0219,	# 	LATIN SMALL LETTER S WITH COMMA BELOW
-	0x00bc: 0x0152,	# 	LATIN CAPITAL LIGATURE OE
-	0x00bd: 0x0153,	# 	LATIN SMALL LIGATURE OE
-	0x00be: 0x0178,	# 	LATIN CAPITAL LETTER Y WITH DIAERESIS
-	0x00bf: 0x017c,	# 	LATIN SMALL LETTER Z WITH DOT ABOVE
-	0x00c3: 0x0102,	# 	LATIN CAPITAL LETTER A WITH BREVE
-	0x00c5: 0x0106,	# 	LATIN CAPITAL LETTER C WITH ACUTE
-	0x00d0: 0x0110,	# 	LATIN CAPITAL LETTER D WITH STROKE
-	0x00d1: 0x0143,	# 	LATIN CAPITAL LETTER N WITH ACUTE
-	0x00d5: 0x0150,	# 	LATIN CAPITAL LETTER O WITH DOUBLE ACUTE
-	0x00d7: 0x015a,	# 	LATIN CAPITAL LETTER S WITH ACUTE
-	0x00d8: 0x0170,	# 	LATIN CAPITAL LETTER U WITH DOUBLE ACUTE
-	0x00dd: 0x0118,	# 	LATIN CAPITAL LETTER E WITH OGONEK
-	0x00de: 0x021a,	# 	LATIN CAPITAL LETTER T WITH COMMA BELOW
-	0x00e3: 0x0103,	# 	LATIN SMALL LETTER A WITH BREVE
-	0x00e5: 0x0107,	# 	LATIN SMALL LETTER C WITH ACUTE
-	0x00f0: 0x0111,	# 	LATIN SMALL LETTER D WITH STROKE
-	0x00f1: 0x0144,	# 	LATIN SMALL LETTER N WITH ACUTE
-	0x00f5: 0x0151,	# 	LATIN SMALL LETTER O WITH DOUBLE ACUTE
-	0x00f7: 0x015b,	# 	LATIN SMALL LETTER S WITH ACUTE
-	0x00f8: 0x0171,	# 	LATIN SMALL LETTER U WITH DOUBLE ACUTE
-	0x00fd: 0x0119,	# 	LATIN SMALL LETTER E WITH OGONEK
-	0x00fe: 0x021b,	# 	LATIN SMALL LETTER T WITH COMMA BELOW
+        0x00a1: 0x0104, #       LATIN CAPITAL LETTER A WITH OGONEK
+        0x00a2: 0x0105, #       LATIN SMALL LETTER A WITH OGONEK
+        0x00a3: 0x0141, #       LATIN CAPITAL LETTER L WITH STROKE
+        0x00a4: 0x20ac, #       EURO SIGN
+        0x00a5: 0x201e, #       DOUBLE LOW-9 QUOTATION MARK
+        0x00a6: 0x0160, #       LATIN CAPITAL LETTER S WITH CARON
+        0x00a8: 0x0161, #       LATIN SMALL LETTER S WITH CARON
+        0x00aa: 0x0218, #       LATIN CAPITAL LETTER S WITH COMMA BELOW
+        0x00ac: 0x0179, #       LATIN CAPITAL LETTER Z WITH ACUTE
+        0x00ae: 0x017a, #       LATIN SMALL LETTER Z WITH ACUTE
+        0x00af: 0x017b, #       LATIN CAPITAL LETTER Z WITH DOT ABOVE
+        0x00b2: 0x010c, #       LATIN CAPITAL LETTER C WITH CARON
+        0x00b3: 0x0142, #       LATIN SMALL LETTER L WITH STROKE
+        0x00b4: 0x017d, #       LATIN CAPITAL LETTER Z WITH CARON
+        0x00b5: 0x201d, #       RIGHT DOUBLE QUOTATION MARK
+        0x00b8: 0x017e, #       LATIN SMALL LETTER Z WITH CARON
+        0x00b9: 0x010d, #       LATIN SMALL LETTER C WITH CARON
+        0x00ba: 0x0219, #       LATIN SMALL LETTER S WITH COMMA BELOW
+        0x00bc: 0x0152, #       LATIN CAPITAL LIGATURE OE
+        0x00bd: 0x0153, #       LATIN SMALL LIGATURE OE
+        0x00be: 0x0178, #       LATIN CAPITAL LETTER Y WITH DIAERESIS
+        0x00bf: 0x017c, #       LATIN SMALL LETTER Z WITH DOT ABOVE
+        0x00c3: 0x0102, #       LATIN CAPITAL LETTER A WITH BREVE
+        0x00c5: 0x0106, #       LATIN CAPITAL LETTER C WITH ACUTE
+        0x00d0: 0x0110, #       LATIN CAPITAL LETTER D WITH STROKE
+        0x00d1: 0x0143, #       LATIN CAPITAL LETTER N WITH ACUTE
+        0x00d5: 0x0150, #       LATIN CAPITAL LETTER O WITH DOUBLE ACUTE
+        0x00d7: 0x015a, #       LATIN CAPITAL LETTER S WITH ACUTE
+        0x00d8: 0x0170, #       LATIN CAPITAL LETTER U WITH DOUBLE ACUTE
+        0x00dd: 0x0118, #       LATIN CAPITAL LETTER E WITH OGONEK
+        0x00de: 0x021a, #       LATIN CAPITAL LETTER T WITH COMMA BELOW
+        0x00e3: 0x0103, #       LATIN SMALL LETTER A WITH BREVE
+        0x00e5: 0x0107, #       LATIN SMALL LETTER C WITH ACUTE
+        0x00f0: 0x0111, #       LATIN SMALL LETTER D WITH STROKE
+        0x00f1: 0x0144, #       LATIN SMALL LETTER N WITH ACUTE
+        0x00f5: 0x0151, #       LATIN SMALL LETTER O WITH DOUBLE ACUTE
+        0x00f7: 0x015b, #       LATIN SMALL LETTER S WITH ACUTE
+        0x00f8: 0x0171, #       LATIN SMALL LETTER U WITH DOUBLE ACUTE
+        0x00fd: 0x0119, #       LATIN SMALL LETTER E WITH OGONEK
+        0x00fe: 0x021b, #       LATIN SMALL LETTER T WITH COMMA BELOW
 })
 
 ### Encoding Map
diff --git a/Lib/encodings/tis_620.py b/Lib/encodings/tis_620.py
index 2ebf311..6e1229e 100644
--- a/Lib/encodings/tis_620.py
+++ b/Lib/encodings/tis_620.py
@@ -38,7 +38,7 @@
 
 decoding_map = decoding_map.copy()
 decoding_map.update({
-	0x00a0: None,
+        0x00a0: None,
 })
 
 ### Encoding Map
diff --git a/Lib/test/test_threadsignals.py b/Lib/test/test_threadsignals.py
index fa58d76..fcae312 100644
--- a/Lib/test/test_threadsignals.py
+++ b/Lib/test/test_threadsignals.py
@@ -69,7 +69,7 @@
 
 def test_main():
     global signal_blackboard
-    
+
     signal_blackboard = { signal.SIGUSR1 : {'tripped': 0, 'tripped_by': 0 },
                           signal.SIGUSR2 : {'tripped': 0, 'tripped_by': 0 },
                           signal.SIGALRM : {'tripped': 0, 'tripped_by': 0 } }