RegEx Help

[mp3909]

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import re dummy = re.compile('XXX\WYYY') mo = dummy.search('the letters XXX\YYY') mo.group()

Can someone please explain why

1	mo.group()

kicks back

1	'XXX\\YYY'

- I thought it should kick back

1

'XXX\YYY'

i.e. just 1 backslash in between the letters not 2.

[snippsat]

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>>> import re >>> dummy = re.compile('XXX\WYYY') >>> mo = dummy.search('the letters XXX\YYY')   >>> mo.group() 'XXX\\YYY' >>> # It magically goes away with print() >>> print(mo.group()) XXX\YYY >>> # No really >>> print(repr(mo.group())) 'XXX\\YYY' >>>

It's this way because of escape characters.
Example \n it's a newline character.
We see only one \,because it's a escape character.

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>>> s = '\n' >>> s '\n' >>> print(s)     >>>

\Y is not a escape character.

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>>> s = '\Y' >>> s '\\Y' >>> print(s) \Y >>>

Also a tip for regex should always use raw string in expression,then will not get a surprise with escape character.
Then it look like this:
dummy = re.compile(r'XXX\WYYY')