---input---
f'*{n=!r:30}*'

---tokens---
'f'           Literal.String.Affix
"'"           Literal.String.Single
'*'           Literal.String.Single
'{'           Literal.String.Interpol
'n'           Name
'=!r:'        Literal.String.Interpol
'30'          Literal.String.Single
'}'           Literal.String.Interpol
'*'           Literal.String.Single
"'"           Literal.String.Single
'\n'          Text.Whitespace