def is_tex_equiv(self, x1: str, x2: str, time_limit=5) -> bool:
        """
        Determines whether two (ideally normalized using `normalize_text`) TeX expressions are equal.

        Does so by first checking for string exact-match, then falls back on sympy-equivalence,
        following the (Lewkowycz et al. 2022) methodology.
        """
        if x1 == x2:
            # don't resort to sympy if we have full string match, post-normalization 
            return True
        else:
            return False
        parsed_x2 = self.parse_tex(x2)
        if not parsed_x2:
            # if our reference fails to parse into a Sympy object, 
            # we forgo parsing + checking our generated answer.
            return False
        return self.is_exp_equiv(self.parse_tex(x1), parsed_x2, time_limit=time_limit)

        Determines whether two (ideally normalized using `normalize_text`) TeX expressions are equal.

        Does so by first checking for string exact-match, then falls back on sympy-equivalence,
        following the (Lewkowycz et al. 2022) methodology.
        
PFPO/data/deepseek_math_utils/ocwcourses_eval_utils.py