Deprecation warning due to invalid escape sequences in Python 3.7

[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 -Ev 'example|utl|samples|deps' | xargs -P 4 -I{} python3.8 -Wall -m py_compile {} 
./test.py:36: DeprecationWarning: invalid escape sequence \,
  self.assertEqual(s, "a\,b\|c\=d")
./test.py:46: DeprecationWarning: invalid escape sequence \|
  self.assertEqual(s, "baz=ba\\r,qu\|ux|foo=a\,s\=df")