Deprecation warning due to invalid escape sequences

[tirkarthi]

Deprecation warnings are raised due to invalid escape sequences. This can be fixed by using raw strings or escaping the literals. pyupgrade also helps in automatic conversion : https://github.com/asottile/pyupgrade/

find . -iname '*.py' | grep -v example | xargs -P4 -I{} python3.8 -Wall -m py_compile {}   
./pyutilib/component/config/tests/test_options.py:155: DeprecationWarning: invalid escape sequence \<
  if re.match("\<Option \[globals\] 'o1'\>",
./pyutilib/component/config/tests/test_options.py:160: DeprecationWarning: invalid escape sequence \<
  re.match("\<Option \[globals\] 'o1'\>", str(ep.service("o1"))) is
./pyutilib/component/config/tests/test_options.py:163: DeprecationWarning: invalid escape sequence \<
  re.match("\<Option \[foo\] 'o2'\>", str(ep.service("o2"))) is None)
./pyutilib/th/runtests.py:212: DeprecationWarning: invalid escape sequence \.
  p = re.compile('^.*TEST-(.+)\.xml')
./pyutilib/misc/log_config.py:15: DeprecationWarning: invalid escape sequence \s
  _indention = re.compile('\s*')
./pyutilib/misc/tests/test_misc.py:208: DeprecationWarning: invalid escape sequence \ 
  ans = pyutilib.misc.quote_split(' ', "a b\ c")
./pyutilib/misc/tests/test_misc.py:209: DeprecationWarning: invalid escape sequence \ 
  self.assertEqual(ans, ["a", 'b\ c'])
./pyutilib/misc/tests/test_config.py:1076: DeprecationWarning: invalid escape sequence \{
  stripped_reference = re.sub('\{[^\}]*\}','',reference,flags=re.M)
./pyutilib/misc/config.py:10: DeprecationWarning: invalid escape sequence \h
  """=================================
./pyutilib/misc/misc.py:153: DeprecationWarning: invalid escape sequence \s
  whitespace_re = re.compile('\s+')
./pyutilib/misc/misc.py:157: DeprecationWarning: invalid escape sequence \s
  """
./pyutilib/dev/tests/test_runtests.py:30: DeprecationWarning: invalid escape sequence \S
  g = re.match('(\S+) \(([^\)]+)\)', line)