Regular Expressions 101

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"
(?P<l>\d+(\,\d+)?)\s*x\s*(?P<w>\d+(\,\d+)?)\s*x\s*(?P<h>\d+(\,\d+)?)
"
g
Named Capture Group l
(?P<l>\d+(\,\d+)?)
\d
matches a digit (equivalent to [0-9])
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
2nd Capturing Group
(\,\d+)?
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
\, matches the character , with index 4410 (2C16 or 548) literally (case sensitive)
\d
matches a digit (equivalent to [0-9])
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
\s
matches any whitespace character (equivalent to [\r\n\t\f\v  ])
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
x matches the character x with index 12010 (7816 or 1708) literally (case sensitive)
\s
matches any whitespace character (equivalent to [\r\n\t\f\v  ])
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
Named Capture Group w
(?P<w>\d+(\,\d+)?)
\d
matches a digit (equivalent to [0-9])
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
4th Capturing Group
(\,\d+)?
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
\, matches the character , with index 4410 (2C16 or 548) literally (case sensitive)
\d
matches a digit (equivalent to [0-9])
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
\s
matches any whitespace character (equivalent to [\r\n\t\f\v  ])
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
x matches the character x with index 12010 (7816 or 1708) literally (case sensitive)
\s
matches any whitespace character (equivalent to [\r\n\t\f\v  ])
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
Named Capture Group h
(?P<h>\d+(\,\d+)?)
\d
matches a digit (equivalent to [0-9])
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
6th Capturing Group
(\,\d+)?
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
\, matches the character , with index 4410 (2C16 or 548) literally (case sensitive)
\d
matches a digit (equivalent to [0-9])
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
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

Code Generator

Generated Code

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Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report.
For a full regex reference for Python, please visit: https://docs.python.org/3/library/re.html