What is a "raw string regex" and how can you use it?
In Python, a raw string is a string prefixed with the letter 'r' or 'R'. Raw strings are used to indicate that the backslash character ('') should not be interpreted as an escape character. This is useful when you want to use a backslash character in a regular expression pattern without having it treated as a special character.
For example, the following regular expression pattern would match any line that contains the word "the":
r"the"
However, the following regular expression pattern would match any line that contains the character '' followed by the word "the":
"\the"
This is because the backslash character is interpreted as an escape character in the second pattern. To match any line that contains the character '' followed by the word "the", you would need to use a raw string:
r"\the"
Raw strings can also be used to match other special characters, such as newline characters (n) and tab characters (t). For example, the following regular expression pattern would match any line that contains the newline character:
r"\n"
And the following regular expression pattern would match any line that contains the tab character:
r"\t"
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