Regular Expressions 101

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"
u'([^']+)': u'([^']+)'
"
g
u'
matches the characters u' literally (case sensitive)
1st Capturing Group
([^']+)
Match a single character not present in the list below
[^']
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
' matches the character ' with index 3910 (2716 or 478) literally (case sensitive)
': u'
matches the characters ': u' literally (case sensitive)
2nd Capturing Group
([^']+)
Match a single character not present in the list below
[^']
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
' matches the character ' with index 3910 (2716 or 478) literally (case sensitive)
' matches the character ' with index 3910 (2716 or 478) literally (case sensitive)
Global pattern flags
g modifier: global. All matches (don't return after first match)
Your regular expression does not match the subject string.

Regular Expression
No Match

r"
"
g

Test String