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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 validate_obj(keys, obj):
 """Super simple "object" validation."""

    msg = ''
    for k in keys:
        if isinstance(k, str):
            if k not in obj or (not isinstance(obj[k], list) and not obj[k]):
                if msg:
                    msg = "%s," % msg

                msg = "%s%s" % (msg, k)
        elif isinstance(k, list):
            found = False
            for k_a in k:
                if k_a in obj:
                    found = True

            if not found:
                if msg:
                    msg = "%s," % msg

                msg = "%s(%s" % (msg, ','.join(k))

    if msg:
        msg = "%s missing" % msg

    return msg