The subject of regular expressions is quite deep, and it takes an immense amount of practice to get used to the special character syntax. Furthermore, the re module contains a vast set of methods available for performing searches using regular expressions. Upon completing the examples in this section, you should have a much deeper appreciation for how powerful regular expressions can be.
IGNORECASE causes literal characters and character ranges in the pattern to match both uppercase and lowercase characters.
Since the pattern includes the literal
IGNORECASE is not set, the only match is the word
This. When case is ignored,
text also matches.