code: def t_quotedvar_ENCAPSED_AND_WHITESPACE(t):
      r'( [^"\\${] | \\(.|\n) | \$(?![A-Za-z_{]) | \{(?!\$) )+'
      t.lexer.lineno += t.value.count("\n")
      t.lexer.pop_state()
      return f t_quotedvar_ENCAPSED_AND_WHITESPACE(t):
      r'( [^"\\${] | \\(.|\n) | \$(?![A-Za-z_{]) | \{(?!\$) )+'
      t.lexer.lineno += t.value.count("\n")
      t.lexer.pop_state()
      return t
docs: r'( [^"\\${] | \\(.|\n) | \$(?![A-Za-z_{]) | \{(?!\$) )+