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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):
 """ Checks current usage against configured thresholds for all limits for this service. :returns: a dict of limit name to :py:class:`~.AwsLimit` instance for all limits that crossed one or more of their thresholds. :rtype: :py:obj:`dict` of :py:class:`~.AwsLimit` """

        if not self._have_usage:
            self.find_usage()
        ret = {}
        for name, limit in self.limits.items():
            if limit.check_thresholds() is False:
                ret[name] = limit
        return ret