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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 _info(message):
 """Convenience function to log current span values. """

    span = values()
    _log.debug(message + ": {span} in trace {trace}. (Parent span: {parent}).".format(
        span=span.get(b3_span_id),
        trace=span.get(b3_trace_id),
        parent=span.get(b3_parent_span_id),
    ))