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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 create_keys_in():
 """ Create a grammer for the 'KEYS IN' clause used for queries """

    keys = Group(
        Optional(Suppress("("))
        + value
        + Optional(Suppress(",") + value)
        + Optional(Suppress(")"))
    )
    return (Suppress(upkey("keys") + upkey("in")) + delimitedList(keys)).setResultsName(
        "keys_in"
    )