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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 build_sanitiser_node_dict( cfg, sinks_in_file ):
 """Build a dict of string -> TriggerNode pairs, where the string is the sanitiser and the TriggerNode is a TriggerNode of the sanitiser. Args: cfg(CFG):
 cfg to traverse. sinks_in_file(list[TriggerNode]):
 list of TriggerNodes containing the sinks in the file. Returns: A string -> TriggerNode dict. """

    sanitisers = list()
    for sink in sinks_in_file:
        sanitisers.extend(sink.sanitisers)

    sanitisers_in_file = list()
    for sanitiser in sanitisers:
        for cfg_node in cfg.nodes:
            if sanitiser in cfg_node.label:
                sanitisers_in_file.append(Sanitiser(sanitiser, cfg_node))

    sanitiser_node_dict = dict()
    for sanitiser in sanitisers:
        sanitiser_node_dict[sanitiser] = list(find_sanitiser_nodes(
            sanitiser,
            sanitisers_in_file
        ))
    return sanitiser_node_dict