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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def check_thresholds(self):
 """ Check this limit's current usage against the specified default thresholds, and any custom theresholds that have been set on the class instance. Return True if usage is within thresholds, or false if warning or critical thresholds have been surpassed. This method sets internal variables in this instance which can be queried via :py:meth:`~.get_warnings` and :py:meth:`~.get_criticals` to obtain further details about the thresholds that were crossed. **Note** This function returns False if *any* thresholds were crossed. Please be aware of this when setting threshold overrides to suppress alerts. Each threshold (``warn_percent``, ``warn_count``, ``crit_percent``, ``crit_count``) that has been set is evaluated individually and the result appended to a list of warnings or criticals, respectively. If *any* of these evaluations failed, the method returns False. :returns: False if any thresholds were crossed, True otherwise :rtype: bool """

        (warn_int, warn_pct, crit_int, crit_pct) = self._get_thresholds()
        all_ok = True
        for u in self._current_usage:
            usage = u.get_value()
            limit = u.get_maximum() or self.get_limit()
            if limit is None:
                continue
            pct = (usage / (limit * 1.0)) * 100
            if crit_int is not None and usage >= crit_int:
                self._criticals.append(u)
                all_ok = False
            elif pct >= crit_pct:
                self._criticals.append(u)
                all_ok = False
            elif warn_int is not None and usage >= warn_int:
                self._warnings.append(u)
                all_ok = False
            elif pct >= warn_pct:
                self._warnings.append(u)
                all_ok = False
        return all_ok