Python 3.0 Print Oddity


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So I tried out the python doc’s code sample for HTMLParser in the shell, but modified it a bit for Python 3.0 and also my own purposes.  It seems like if you just re-run the class in IDLE, the behavior will update but old print statements will persist.  So strange! I wonder why?

from html.parser import HTMLParserclass MyHTMLParser(HTMLParser):    def handle_starttag(self, tag, attrs):        if tag == 'p':            print ("Encountered a P tag:", tag)            print ("Attrib:", attrs)    def handle_endtag(self, tag):        if tag == 'p':            print ("Encountered  an end P tag:", tag)    def handle_data(self, data):        print ("Encountered   some data:", data)parser = MyHTMLParser()parser.feed('<html><head><title>Test</title></head>'            '<body><h1><p>Parse me!</p></h1></body></html>')

Looks like the correct behaviour, but why does the original print output get displayed?

Encountered   some data: Test
Encountered a start tag: p
Encountered   some data: Parse me!
Encountered  an end tag: p

This must be some residue of the previous Python version, although the docs suggest I should be able to do everything as before except wrap print parameters with the parentheses.  

 

Old: print "The answer is", 2*2New: print("The answer is", 2*2)

 

I guess in Python 3+, only the str.format is safe to use for all occassions — at the moment.  

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