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diff --git a/prolog/problems/denotational_semantics/prog_listswap_2/en.py b/prolog/problems/denotational_semantics/prog_listswap_2/en.py
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+id = 175
+name = 'prog_listswap/2'
+slug = 'list-manipulation language'
+
+description = '''\
+<p>Write a DCG for manipulating list elements. The first symbol in every word is <code>[begin]</code>, followed by any sequence of "instruction" symbols from the set {<code>left</code>, <code>right</code>, <code>swap</code>}, and finally <code>[end]</code>. The starting symbol should be named <code>prog_listswap</code>.</p>
+
+<p>Example words: <code>[begin,right,swap,end]</code>, <code>[begin,right,left,end]</code>.</p>
+'''
+
+hint = {}