# SyntaxError: f-string expression part cannot include a backslash

---input---
f'{\'quoted string\'}'

---tokens---
'f'           Literal.String.Affix
"'"           Literal.String.Single
'{'           Literal.String.Interpol
'\\'          Error
"'"           Literal.String.Single
'quoted string' Literal.String.Single
"\\'"         Literal.String.Escape
'}'           Literal.String.Single
"'"           Literal.String.Single
'\n'          Text
