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    <p>It sounds like you're just trying to add a string to a list of strings. That's just <code>append</code>:</p> <pre><code>&gt;&gt;&gt; inside = ['thing', 'other thing'] &gt;&gt;&gt; inside.append('another thing') &gt;&gt;&gt; inside ['thing', 'other thing', 'another thing'] </code></pre> <p>There's nothing specific here to strings; the same thing works for a list of <code>Item</code> instances, or a list of lists of lists of strings, or a list of 37 different things of 37 different types.</p> <p>In general, <code>append</code> is the most efficient way to concatenate a single thing onto the end of a list. If you want to concatenate a bunch of things, and you already have them in a list (or iterator or other sequence), instead of doing them one at a time, use <code>extend</code> to do them all at once, or just <code>+=</code> instead (which means the same thing as <code>extend</code> for lists):</p> <pre><code>&gt;&gt;&gt; inside = ['thing', 'other thing'] &gt;&gt;&gt; in_hand = ['sword', 'lamp'] &gt;&gt;&gt; inside += in_hand &gt;&gt;&gt; inside ['thing', 'other thing', 'sword', 'lamp'] </code></pre> <p>If you want to later concatenate that list of strings into a single string, that's the <code>join</code> method, as RocketDonkey explains:</p> <pre><code>&gt;&gt;&gt; ', '.join(inside) 'thing, other thing, another thing' </code></pre> <p>I'm guessing you want to get a little fancier and put an "and" between the last to things, skip the commas if there are fewer than three, etc. But if you know how to slice a list and how to use <code>join</code>, I think that can be left as an exercise for the reader.</p> <p>If you're trying to go the other way around and concatenate a list to a string, you need to turn that list into a string in some way. You can just use <code>str</code>, but often that won't give you what you want, and you'll want something like the <code>join</code> example above.</p> <p>At any rate, once you have the string, you can just add it to the other string:</p> <pre><code>&gt;&gt;&gt; 'Inside = ' + str(inside) "Inside = ['thing', 'other thing', 'sword', 'lamp']" &gt;&gt;&gt; 'Inside = ' + ', '.join(inside) 'Inside = thing, other thing, another thing' </code></pre> <p>If you have a list of things that aren't strings and want to add them to the string, you have to decide on the appropriate string representation for those things (unless you're happy with <code>repr</code>):</p> <pre><code>&gt;&gt;&gt; class Item(object): ... def __init__(self, desc): ... self.desc = desc ... def __repr__(self): ... return 'Item(' + repr(self.desc) + ')' ... def __repr__(self): ... return self.desc ... &gt;&gt;&gt; inside = [Item('thing'), Item('other thing')] &gt;&gt;&gt; 'Inside = ' + repr(inside) ... "Inside = [Item('thing'), Item('other thing')]" &gt;&gt;&gt; 'Inside = ' + str(inside) ... "Inside = [Item('thing'), Item('other thing')]" &gt;&gt;&gt; 'Inside = ' + ', '.join(str(i) for i in inside) ... 'Inside = thing, other thing' </code></pre> <p>Notice that just calling <code>str</code> on a list of <code>Item</code>s calls <code>repr</code> on the individual items; if you want to call <code>str</code> on them, you have to do it explicitly; that's what the <code>str(i) for i in inside</code> part is for.</p> <p>Putting it all together:</p> <pre><code>class Backpack: def __init__(self): self.inside = [] def add(self, toadd): self.inside.append(toadd) def addmany(self, listtoadd): self.inside += listtoadd def __str__(self): return ', '.join(str(i) for i in self.inside) pack = Backpack() pack.add('thing') pack.add('other thing') pack.add('another thing') print 'Your backpack contains:', pack </code></pre> <p>When you run this, it will print:</p> <pre><code>Your backpack contains: thing, other thing, another thing </code></pre>
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    1. POGood way to concatenate str to list?
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    1. COI'm really trying to add a list of `Item`s to a string, so that might comlpicate things
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    2. COYou need to define what it means to turn an `Item`, or a list of `Items`, into a string. Once you do that, adding it to a string is easy. I'll edit my answer to give more details.
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    3. COHa, +1 because I just realized that my edit overlapped with what you mentioned in your first section :) Sorry for the repeat.
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