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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 param_fetch_all(self):
        '''initiate fetch of all parameters'''
        if time.time() - getattr(self, 'param_fetch_start', 0) < 2.0:
            # don't fetch too often
            return
        self.param_fetch_start = time.time()
        self.param_fetch_in_progress = True
        self.mav.param_request_list_send(self.target_system, self.target_component)