Python | Special characters in python regex

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Regex metacharacters

Regular expression (regex) metacharacters are special characters that have a specific meaning when used in a regex pattern. Here are some commonly used regex metacharacters:

. (dot): Matches any single character except for a newline character.
^ (caret): Matches the start of a string.
$ (dollar sign): Matches the end of a string.
[] (square brackets): Matches any single character within the brackets. For example, the pattern [abc] matches a, b, or c.
| (pipe): Matches either the expression before or after the pipe. For example, the pattern cat|dog matches cat or dog.
() (parentheses): Groups parts of a pattern together. This is useful for applying a quantifier to a group of characters. For example, the pattern (abc)+ matches one or more occurrences of the sequence abc.
* (asterisk): Matches zero or more occurrences of the preceding character or group.
+ (plus): Matches one or more occurrences of the preceding character or group.
? (question mark): Matches zero or one occurrence of the preceding character or group.
{} (curly braces): Matches a specific number of occurrences of the preceding character or group. For example, the pattern a{3} matches exactly three a's.
\ (backslash): Escapes special characters so that they are treated literally. For example, to match a literal . character, you would use the pattern \..

These are just a few examples of regex metacharacters, and there are many more available depending on the flavor of regex you are using.