added quote from PEP 3101

strings.html

@@ -191,7 +191,7 @@ def approximate_size(size, a_kilobyte_is_1024_bytes=True):
 <ul>
 <li>The <code>sys</code> module holds information about the currently running Python instance. Since you just imported it, you can pass the <code>sys</code> module itself as an argument to the <code>format()</code> method. So the replacement field <code>{0}</code> refers to the <code>sys</code> module.
 <li><code>sys.modules</code> is a dictionary of all the modules that have been imported in this Python instance. The keys are the module names as strings; the values are the module objects themselves. So the replacement field <code>{0.modules}</code> refers to the dictionary of imported modules.
-<li><code>sys.modules['humansize']</code> is the <code>humansize</code> module which you just imported. The replacement field <code>{0.modules[humansize]}</code> refers to the <code>humansize</code> module. Note the slight difference in syntax here. In real Python code, the keys of the <code>sys.modules</code> dictionary are strings; to refer to them, you need to put quotes around the module name (<i>e.g.</i> <code>'humansize'</code>). But within a replacement field, you skip the quotes around the dictionary key name (<i>e.g.</i> <code>humansize</code>).
+<li><code>sys.modules['humansize']</code> is the <code>humansize</code> module which you just imported. The replacement field <code>{0.modules[humansize]}</code> refers to the <code>humansize</code> module. Note the slight difference in syntax here. In real Python code, the keys of the <code>sys.modules</code> dictionary are strings; to refer to them, you need to put quotes around the module name (<i>e.g.</i> <code>'humansize'</code>). But within a replacement field, you skip the quotes around the dictionary key name (<i>e.g.</i> <code>humansize</code>). To quote <a href=http://www.python.org/dev/peps/pep-3101/>PEP 3101: Advanced String Formatting</a>, &#8220;The rules for parsing an item key are very simple. If it starts with a digit, then it is treated as a number, otherwise it is used as a string.&#8221;
 <li><code>sys.modules['humansize'].SUFFIXES</code> is the dictionary defined at the top of the <code>humansize</code> module. The replacement field <code>{0.modules[humansize].SUFFIXES}</code> refers to that dictionary.
 <li><code>sys.modules['humansize'].SUFFIXES[1000]</code> is a list of <abbr>SI</abbr> suffixes: <code>['KB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB']</code>. So the replacement field <code>{0.modules[humansize].SUFFIXES[1000]}</code> refers to that list.
 <lI><code>sys.modules['humansize'].SUFFIXES[1000][0]</code> is the first item of the list of <abbr>SI</abbr> suffixes: <code>'KB'</code>. Therefore, the complete replacement field <code>{0.modules[humansize].SUFFIXES[1000][0]}</code> is replaced by the two-character string <code>KB</code>.

util/lesscss.py

@@ -7,7 +7,7 @@ import sys
 # These selectors are kept regardless of whether this script thinks they are used.
 # Most of these match nodes that are dynamically inserted or manipulated by script
 # after the page has loaded, which is why a static analysis thinks they're unused.
-SELECTOR_EXCEPTIONS = ('.w', '.b', '.str', '.kwd', '.com', '.typ', '.lit', '.pun', '.tag', '.atn', '.atv', '.dec', 'pre span.u', 'pre span.u span')
+SELECTOR_EXCEPTIONS = ('.w', '.b', '.str', '.kwd', '.com', '.typ', '.lit', '.pun', '.tag', '.atn', '.atv', '.dec', 'pre .u', 'pre .u span')
 
 filename = sys.argv[1]
 pqd = pq(filename=filename)