We can select string with some patterns.
.matches any character except a newline
^aall strings starting with'a'
a$all strings ending with'a'
ab+matches'ab','abb'but not'a','ac'.
[bcr]atany characters within[]can be filled the space
- Using
\\to escape special characters \\s: whitespace characters.\\S: any except whitespace.\\b: empty strings (only at the beginning or end of a word).\\B:
cat|dogwould match'catfish'and'hotdog'for begin and end characters
[amk]will match'a','m', or `'k``
[0-9]will match any character that falls between0and9
[a-z]: lowercase
[0-9]{4}: repeat the pattern[0-9]four times by writing
a{m,n}matches frommtonrepetitions of'a'.a{m,}matches frommto infinity repetitions of'a'.
- Python docs -- Regular Expression.