解释以下绕口令的意思。


"Peter Piper picked a peck of pickled peppers.
A peck of pickled peppers Peter Piper picked.
If Peter Piper picked a peck of pickled peppers,
Where's the peck of pickled peppers Peter Piper picked?"
这个绕口令是描述Peter Piper摘了一袋子的腌制辣椒，但在最后问题中问到这袋子辣椒到底去了哪里。