def get_distance(self, latitude: float, longitude: float) -> float:
lat1 = math.radians(latitude)
lon1 = math.radians(longitude)
lat2 = math.radians(self.latitude)
lon2 = math.radians(self.longitude)
return 2 * self.R * math.asin(math.sqrt(math.sin((lat2 - lat1) / 2) ** 2 + math.cos(lat1) * math.cos(lat2) * math.sin((lon2 - lon1) / 2) ** 2))
secret = Signer().sign(inventory_id)
url = f'{self.BASE_URL}/inventory/{secret}'