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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_datas(callback, macs=[], run_flag=RunFlag(), bt_device=''):
 """ Get data for all ruuvitag sensors or sensors in the MAC's list. Args: callback (func):
 callback funcion to be called when new data is received macs (list):
 MAC addresses run_flag (object):
 RunFlag object. Function executes while run_flag.running bt_device (string):
 Bluetooth device id """


        log.info('Get latest data for sensors. Stop with Ctrl+C.')
        log.info('MACs: %s', macs)

        for new_data in RuuviTagSensor._get_ruuvitag_datas(macs, None, run_flag, bt_device):
            callback(new_data)