PyRegex\ escape special characters . matches any character ^ matches beginning of string $ matches end of string [5b-d] matches any chars '5', 'b', 'c' or 'd' [^a-c6] matches any char except 'a', 'b', 'c' or '6' R|S matches either regex R or regex S () creates a capture group and indicates precedence * 0 or more (append ? for non-greedy) + 1 or more (append ? for non-greedy) ? 0 or 1 (append ? for non-gr
