python: cleanup with autopep8

* tests/python/341.py, tests/python/alarm.py, tests/python/bdddict.py,
tests/python/bddnqueen.py, tests/python/bugdet.py,
tests/python/dualize.py, tests/python/except.py, tests/python/gen.py,
tests/python/genem.py, tests/python/implies.py,
tests/python/interdep.py, tests/python/ipnbdoctest.py,
tests/python/kripke.py, tests/python/ltl2tgba.py,
tests/python/ltlf.py, tests/python/ltlparse.py,
tests/python/ltlsimple.py, tests/python/relabel.py,
tests/python/rs_like.py, tests/python/sccsplit.py,
tests/python/semidet.py, tests/python/setacc.py,
tests/python/setxor.py, tests/python/split.py,
tests/python/streett_totgba.py, tests/python/stutter.py,
tests/python/sum.py, tests/python/toparity.py, tests/python/toweak.py,
tests/python/trival.py, python/spot/__init__.py, python/spot/aux.py,
python/spot/jupyter.py: Reformat with autopep8.

fixup! * spot/tl/simplify.cc: Fix typos in tracing code.

tests/python/bddnqueen.py

@@ -1,5 +1,5 @@
 # -*- mode: python; coding: utf-8 -*-
-# Copyright (C) 2010, 2011, 2012, 2014 Laboratoire de Recherche et
+# Copyright (C) 2010, 2011, 2012, 2014, 2019 Laboratoire de Recherche et
 # Développement de l'EPITA.
 # Copyright (C) 2003, 2004 Laboratoire d'Informatique de Paris 6
 # (LIP6), département Systèmes Répartis Coopératifs (SRC), Université
@@ -26,9 +26,12 @@
 import sys
 from buddy import *
 
-# Build the requirements for all other fields than (i,j) assuming
-# that (i,j) has a queen.
+
 def build(i, j):
+    """
+    Build the requirements for all other fields than (i,j) assuming
+    that (i,j) has a queen.
+    """
     a = b = c = d = bddtrue
 
     # No one in the same column.
@@ -59,7 +62,6 @@ def build(i, j):
     queen &= a & b & c & d
 
 
-
 # Get the number of queens from the command-line, or default to 8.
 if len(sys.argv) > 1:
     N = int(argv[1])
@@ -97,7 +99,6 @@ solution = bdd_satone(queen)
 bdd_printset(solution)
 
 from spot import nl_cout
-
 nl_cout()
 
 # Cleanup all BDD variables before calling bdd_done(), otherwise