code: def set_enabled(self, enabled):
          
          enabled_bit = '1' if enabled else '0'
          self.trace_options_byte = str(
              self.trace_options_byte)[:-1] + enabled_bit
          self.enabled = self.get_enabled
docs: Update the last bit of the trace options byte str.
  
          :type enabled: bool
          :param enabled: Whether enable tracing in this span context or not.