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How to get multiple matches with difflib.SequenceMatcher?

I use difflib to identify all short string matches in a longer sequence. However, it seems that when there are several matches, difflib returns only one:

> sm = difflib.SequenceMatcher(None, a='ACT', b='ACTGACT')
> sm.get_matching_blocks()
[Match(a=0, b=0, size=3), Match(a=3, b=7, size=0)]

Expected Result:

[Match(a=0, b=0, size=3), Match(a=0, b=4, size=3), Match(a=3, b=7, size=0)]

In fact, the ACTGACT line contains two ACT matches, at positions 0 and 4, both of size 3 (plus another match of size 0 at the end of the lines).

How can I get some matches? I expected difflib to return both positions.

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difflib ? .

import re
pattern = "ACT"
text = "ACTGACT"
matches = [m.span() for m in re.finditer(pattern, text)]

:

[(0, 3), (4, 7)]

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