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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 normalize_uriparm(p: URIPARM) -> List[URIRef]: """ Return an optional list of URIRefs for p"""

    return normalize_urilist(p) if isinstance(p, List) else \
        normalize_urilist([p]) if isinstance(p, (str, URIRef)) else p