#
# toy example of a self-describing algebraic expression represented by a
# tree of type %sfOZXT
#
#
{qo[qQZwYQ[YR{LlbiXq_sZhRiAoJAeOvq?lBjR?HmT=Z@ygPKm<WXog\vOgJgJdyT{HodX@iXC?yrE
yuV{^a]{qmtzyGSQRYYAxqIQIxiHpg^cxyI>CN^gNe`z=ZIgGwNt=gO@]cyPTXj^pntTTlSaPnWgmP`
oDu{fUoJ`\QNf<=KmoF_xZ\<KwhfdGzOtdSkm\<zy>wFctx`oPqL{Dp@wPgKOL_qlk{Pd?VnwqA\FAt
DQM]oJFZFOuQHbHbSh{ofUnoF[^DS_moF\_\S_ctwFf<=cv<AoxT<HAtc_nNJ[vBqF\<O\APdKv>>]Z
Ve{Dp@t^{t<dS^`wKt^Atuz\=XEz]\@\
