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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 is_not_null_predicate( raw_crash, dumps, processed_crash, processor, key='' ):
 """a predicate that converts the key'd source to boolean. parameters: raw_crash - dict dumps - placeholder in a fat interface - unused processed_crash - placeholder in a fat interface - unused processor - placeholder in a fat interface - unused """

    try:
        return bool(raw_crash[key])
    except KeyError:
        return False