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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 _prune(current, keys):
 """ Reduce the amount of data we have to sift through to only include the specified keys, and children that contain the specified keys """

    pruned_current = {k: current[k] for k in keys if k in current}
    pruned_children = list(
        filter(
            None, [_prune(c, keys) for c in current.get("IORegistryEntryChildren", [])]
        )
    )
    keep_current = any(k in current for k in keys) or pruned_children
    if keep_current:
        if pruned_children:
            pruned_current["IORegistryEntryChildren"] = pruned_children
        return pruned_current
    else:
        return {}