Regular Expressions 101

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"
闹钟|.{0,3}[|早|醒|我|起]+
"
gm
1st Alternative
闹钟
闹钟
matches the characters 闹钟 literally (case sensitive)
2nd Alternative
.{0,3}[|早|醒|我|起]+
matches the character with index 2148310 (53EB16 or 517538) literally (case sensitive)
.
matches any character (except for line terminators)
{0,3} matches the previous token between 0 and 3 times, as many times as possible, giving back as needed (greedy)
Match a single character present in the list below
[|早|醒|我|起]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
|早|醒|我|起
matches a single character in the list |早醒我起 (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