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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 _bfs_from_cluster_tree(tree, bfs_root):
 """ Perform a breadth first search on a tree in condensed tree format """


    result = []
    to_process = [bfs_root]

    while to_process:
        result.extend(to_process)
        to_process = tree['child'][np.in1d(tree['parent'], to_process)].tolist()

    return result