from math import *

class Coordinate:

    def __init__(self, deg_latitude, deg_longitude):
        self.latitude = radians(deg_latitude)
        self.longitude = radians(deg_longitude)

    def distance(self, other):
        dlat = self.latitude - other.latitude
        dlon = self.longitude - other.longitude
        Hav = sin(dlat / 2)**2 + cos(self.latitude) * cos(other.latitude) * sin(dlon / 2)**2
        return 6373 * 2 * atan2(sqrt(Hav), sqrt(1 - Hav))
    
zurich = Coordinate(47.36667, 8.55)
brisbane = Coordinate(-27.46794, 153.02809)
print("Zürich nach Brisbane:", int(zurich.distance(brisbane)))
print("Brisbane nach Zürich:", int(brisbane.distance(zurich)))