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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 log_all(self, file):
 """Log all data received from RFLink to file."""

        global rflink_log
        if file == None:
            rflink_log = None
        else:
            log.debug('logging to: %s', file)
            rflink_log = open(file, 'a')