Regular Expressions 101

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"
Amazon(?![^<]*</a>)
"
gm
Amazon
matches the characters Amazon literally (case sensitive)
Negative Lookahead
(?![^<]*</a>)
Assert that the Regex below does not match
Match a single character not present in the list below
[^<]
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
< matches the character < with index 6010 (3C16 or 748) literally (case sensitive)
</a>
matches the characters </a> literally (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