def read_retry(sensor, pin, retries=15, delay_seconds=2, platform=None):
    """Read DHT sensor of specified sensor type (DHT11, DHT22, or AM2302) on
    specified pin and return a tuple of humidity (as a floating point value
    in percent) and temperature (as a floating point value in Celsius).
    Unlike the read function, this read_retry function will attempt to read
    multiple times (up to the specified max retries) until a good reading can be
    found. If a good reading cannot be found after the amount of retries, a tuple
    of (None, None) is returned. The delay between retries is by default 2
    seconds, but can be overridden.
    """
    for i in range(retries):
        humidity, temperature = read(sensor, pin, platform)
        if humidity is not None and temperature is not None:
            return (humidity, temperature)
        time.sleep(delay_seconds)
    return (None, None)