def get(node, nodeId):
    """
    Get a node with the specified C{nodeId} as any of the C{class},
    C{id} or C{pattern} attributes. If there is no such node, raise
    L{NodeLookupError}.
    """
    result = _get(node, nodeId)
    if result: return result
    raise NodeLookupError(nodeId)

    Get a node with the specified C{nodeId} as any of the C{class},
    C{id} or C{pattern} attributes. If there is no such node, raise
    L{NodeLookupError}.
    
stackoverflow/venv/lib/python3.6/site-packages/twisted/web/domhelpers.py