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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:
 """Apply a mapping function to each File path in the object `rec`."""


    if isinstance(rec, MutableMapping):
        if rec.get("class") == "File":
            rec["path"] = op(rec["path"])
        for d in rec:
            adjustFiles(rec[d], op)
    if isinstance(rec, MutableSequence):
        for d in rec:
            adjustFiles(d, op)