human
Solve the following python programming problem given the following code:
@ rerun_if_locked 
def _delete_stream(self, stream_hash) : 
    d = self.db_conn.runQuery ('select stream_hash from live_streams where stream_hash = ?', (do_delete,)) 
    d.addCallback ((lambda result : (result [0] [0] if len (result) else Failure (NoSuchStreamHashError (stream_hash))))) 
    def do_delete(transaction, s_h) : 
        transaction.execute ('delete from live_streams where stream_hash = ?', (s_h,)) 
        transaction.execute ('delete from live_stream_blobs where stream_hash = ?', (s_h,)) 
        transaction.execute ('delete from live_stream_descriptors where stream_hash = ?', (s_h,)) 
d.addCallback ((lambda s_h : self.db_conn.runInteraction (do_delete, s_h))) 
    return d 

    
    

    Fix the buggy line: d = self.db_conn.runQuery ('select stream_hash from live_streams where stream_hash = ?', (do_delete,))
assistant
#Here is Python code to fix the buggy line: d = self.

d = self.db_conn.runQuery ('select stream_hash from live_streams where stream_hash = ?', (stream_hash,))