Breather models.

CityConditions.swift

struct CityConditions {
    let city: String
    let weather: Weather
    let pollution: Pollution
    let asthma: Asthma
}

struct Weather {
    let timestamp: String // timestamp: ex. "2018-12-04T18:00:00.000Z" (ISO 8601) (Z stands for UTC)
    let iconCode: String // weather icon code: ex. "10n"
    let temperature: Int // temperature: ex. 6 (Celsius)
    let humidity: Int // humidity: 93 (%)
    let pressure: Int // atmospheric pressure: ex. 1022 (hPa)
    let windSpeed: Float // wind speed: ex. 2.26 (m/s)
    let windDirection: Int // wind direction as an angle of 360° (N=0, E=90, S=180, W=270): ex. 145
}

struct Pollution {
    let timestamp: String // timestamp: ex. "2018-12-04T18:00:00.000Z" (ISO 8601) (Z stands for UTC)
    let aqiUS: Int // AQI value based on US EPA standard: ex. 4
    let mainPollutantUS: String // main pollutant for US AQI: ex. "o3"
    let aqiChina: Int // AQI value based on China MEP standard: ex. 3
    let mainPollutantChina: String // main pollutant for Chinese AQI: ex. "o3"
}

struct Asthma {
    let risk: String // risk of adverse respiratory conditions: "high", "medium" or "low"
    let probability: Int // probability of adverse respiratory conditions: ex. 64 (%)
}