Regular Expressions 101

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"
[^@ ]+(?=[#>])
"
gm
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 a single character in the list @ (case sensitive)
Positive Lookahead
(?=[#>])
Assert that the Regex below matches
Match a single character present in the list below
[#>]
#>
matches a single character in the list #> (case sensitive)
Global pattern flags
g modifier: global. All matches (don't return after first match)
m modifier: multi line. Causes ^ and $ to match the begin/end of each line (not only begin/end of string)
Your regular expression does not match the subject string.

Regular Expression
No Match

r"
"
gm

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