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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 _on_report(_loop, adapter, conn_id, report):
 """Callback when a report is received."""


    conn_string = None
    if conn_id is not None:
        conn_string = adapter._get_property(conn_id, 'connection_string')

    if isinstance(report, BroadcastReport):
        adapter.notify_event_nowait(conn_string, 'broadcast', report)
    elif conn_string is not None:
        adapter.notify_event_nowait(conn_string, 'report', report)
    else:
        adapter._logger.debug("Dropping report with unknown conn_id=%s", conn_id)