code: def __str__(self) -> str:
      expr_str = "("
      if self.get_child(0):
          expr_str += f"{str(self.get_child(0))}"
      if self.etype:
          expr_str += f" {str(self.get_symbol())} "
      if self.get_child(1):
          expr_str += f"{str(self.get_child(1))}"
      expr_str += ")"
      return expr_str
  
file_path: evadb/evadb/expression/logical_expression.py
imports: from evadb.expression.abstract_expression import AbstractExpression, ExpressionReturnType, ExpressionType
label_desc: Use image node_id 5 for calling the LogicalExpression obj's underlying member method code with example usage: obj.__str__() and returns: expr_str