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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 update(self):
 """Fetch updated information about devices"""


        if self.device_time_check():

            if not self.in_process:
                outlets, switches, fans = self.get_devices()

                self.outlets = helpers.resolve_updates(self.outlets, outlets)
                self.switches = helpers.resolve_updates(
                    self.switches, switches)
                self.fans = helpers.resolve_updates(self.fans, fans)

                self.last_update_ts = time.time()