Merge 599e806fb1315aef02562c670523834f726d4c83 into 22901bc1db0eb357dc5b2bdc5b2476f97b887b74

README.md

@@ -111,6 +111,8 @@ not match the string `the`.
 
 [Test the regular expression](https://regex101.com/r/1paXsy/1)
 
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 ## 2. Meta Characters
 
 Meta characters are the building blocks of regular expressions.  Meta
@@ -401,6 +403,8 @@ character and the matcher must be at the end of the string.
 
 [Test the regular expression](https://regex101.com/r/t0AkOd/1)
 
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 ##  3. Shorthand Character Sets
 
 There are a number of convenient shorthands for commonly used character sets/
@@ -416,6 +420,8 @@ regular expressions:
 |\s|Matches whitespace characters: `[\t\n\f\r\p{Z}]`|
 |\S|Matches non-whitespace characters: `[^\s]`|
 
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 ## 4. Lookarounds
 
 Lookbehinds and lookaheads (also called lookarounds) are specific types of
@@ -495,6 +501,8 @@ string that are not after the word `The` or `the`.
 
 [Test the regular expression](https://regex101.com/r/8Efx5G/1)
 
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 ## 5. Flags
 
 Flags are also called modifiers because they modify the output of a regular
@@ -574,6 +582,8 @@ at the end of each line in a string.
 
 [Test the regular expression](https://regex101.com/r/E88WE2/1)
 
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 ## 6. Greedy vs Lazy Matching
 By default, a regex will perform a greedy match, which means the match will be as long as
 possible. We can use `?` to match in a lazy way, which means the match should be as short as possible.
@@ -590,6 +600,7 @@ possible. We can use `?` to match in a lazy way, which means the match should be
 
 [Test the regular expression](https://regex101.com/r/AyAdgJ/2)
 
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 ## Contribution