code: def expression(self) -> Expression | None:
      tokens: list[lx.Token] = []
      level = 1
      while tkn := self.peek():
          if tkn.kind in (lx.LBRACKET, lx.LPAREN):
              level += 1
          elif tkn.kind in (lx.RBRACKET, lx.RPAREN):
              level -= 1
              if level == 0:
                  break
          tokens.append(tkn)
          self.next()
      if not tokens:
          return None
      return Expression(lx.to_text(tokens).strip())
  
imports: from dataclasses import dataclass, field
  from typing import NamedTuple, Callable, TypeVar, Literal, cast
  import lexer
  from plexer import PLexer
label_desc: Use image node_id 11 for calling the Parser obj's underlying member method code with example usage: obj.expression() and returns: Expression, None