a = 's t r'
a = u's t r'
a = b's t r'
a = r's t r'
a = br's t r'
a = rb's t r'



a             : source.python
              : source.python
=             : keyword.operator.assignment.python, source.python
              : source.python
'             : punctuation.definition.string.begin.python, source.python, string.quoted.single.python
s t r         : source.python, string.quoted.single.python
'             : punctuation.definition.string.end.python, source.python, string.quoted.single.python
a             : source.python
              : source.python
=             : keyword.operator.assignment.python, source.python
              : source.python
u             : source.python, storage.type.string.python, string.quoted.single.python
'             : punctuation.definition.string.begin.python, source.python, string.quoted.single.python
s t r         : source.python, string.quoted.single.python
'             : punctuation.definition.string.end.python, source.python, string.quoted.single.python
a             : source.python
              : source.python
=             : keyword.operator.assignment.python, source.python
              : source.python
b             : source.python, storage.type.string.python, string.quoted.binary.single.python
'             : punctuation.definition.string.begin.python, source.python, string.quoted.binary.single.python
s t r         : source.python, string.quoted.binary.single.python
'             : punctuation.definition.string.end.python, source.python, string.quoted.binary.single.python
a             : source.python
              : source.python
=             : keyword.operator.assignment.python, source.python
              : source.python
r             : source.python, storage.type.string.python, string.regexp.quoted.single.python
'             : punctuation.definition.string.begin.python, source.python, string.regexp.quoted.single.python
s t r         : source.python, string.regexp.quoted.single.python
'             : punctuation.definition.string.end.python, source.python, string.regexp.quoted.single.python
a             : source.python
              : source.python
=             : keyword.operator.assignment.python, source.python
              : source.python
br            : source.python, storage.type.string.python, string.regexp.quoted.single.python
'             : punctuation.definition.string.begin.python, source.python, string.regexp.quoted.single.python
s t r         : source.python, string.regexp.quoted.single.python
'             : punctuation.definition.string.end.python, source.python, string.regexp.quoted.single.python
a             : source.python
              : source.python
=             : keyword.operator.assignment.python, source.python
              : source.python
rb            : source.python, storage.type.string.python, string.regexp.quoted.single.python
'             : punctuation.definition.string.begin.python, source.python, string.regexp.quoted.single.python
s t r         : source.python, string.regexp.quoted.single.python
'             : punctuation.definition.string.end.python, source.python, string.regexp.quoted.single.python