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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 set_enabled(self, enabled):
 """Update the last bit of the trace options byte str. :type enabled: bool :param enabled: Whether enable tracing in this span context or not. """

        enabled_bit = '1' if enabled else '0'
        self.trace_options_byte = str(
            self.trace_options_byte)[:-1] + enabled_bit
        self.enabled = self.get_enabled