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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 get_bounding_box(self, lon, lat, trt=None, mag=None):
 """ Build a bounding box around the given lon, lat by computing the maximum_distance at the given tectonic region type and magnitude. :param lon: longitude :param lat: latitude :param trt: tectonic region type, possibly None :param mag: magnitude, possibly None :returns: min_lon, min_lat, max_lon, max_lat """

        if trt is None:  # take the greatest integration distance
            maxdist = max(self(trt, mag) for trt in self.dic)
        else:  # get the integration distance for the given TRT
            maxdist = self(trt, mag)
        a1 = min(maxdist * KM_TO_DEGREES, 90)
        a2 = min(angular_distance(maxdist, lat), 180)
        return lon - a2, lat - a1, lon + a2, lat + a1