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round(345, -1) = 350.0
round(345, -3) = 0.0
round(345, 0) = 345.0
round(345.2345, 2) = 345.23000000000002
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from cmd import *
class MyShell(Cmd):
def preloop(self):
print "print this line before entering the loop"
def postloop(self):
&nb ......
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http://chardet.feedparser.org/ ×Ô¶¯¼ì²â±àÂë
http://effbot.org/zone/celementtree.htm cElementTree
http://github.com/jaybaird/python-bloomfilter bloomfilter
http://docs.python.org/library/threading.html#threading.activeCount threading ......