---input---
f"{{{4*10}}}"

---tokens---
'f'           Literal.String.Affix
'"'           Literal.String.Double
'{{'          Literal.String.Escape
'{'           Literal.String.Interpol
'4'           Literal.Number.Integer
'*'           Operator
'10'          Literal.Number.Integer
'}'           Literal.String.Interpol
'}}'          Literal.String.Escape
'"'           Literal.String.Double
'\n'          Text.Whitespace