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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_progress(adapter, operation, conn_id, done, total):
 """Callback when progress is reported."""


    conn_string = adapter._get_property(conn_id, 'connection_string')
    if conn_string is None:
        return

    adapter.notify_progress(conn_string, operation, done, total)