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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 map_indices_root2child(child, root_indices):
 """Map root RTDCBase event indices to child RTDCBase Parameters parent: RTDCBase hierarchy parent of `child`. root_indices: 1d ndarray hierarchy root indices to map (not necessarily the indices of `parent`) Returns ------- child_indices: 1d ndarray child indices """

    # construct hierarchy tree containing only RTDC_Hierarchy instances
    hierarchy = [child]
    while True:
        if isinstance(child.hparent, RTDC_Hierarchy):
            # the parent is a hierarchy tree
            hierarchy.append(child.hparent)
            child = child.hparent
        else:
            break

    indices = root_indices
    for hp in hierarchy[::-1]:  # reverse order
        # For each hierarchy parent, map the indices down the
        # hierarchy tree.
        indices = map_indices_parent2child(child=hp,
                                           parent_indices=indices)
    return indices