Regex Tester & Validator

Matches exactly one word character, which in Python 3 includes letters (a-z, A-Z, and Unicode letters), digits (0-9), and the underscore. With the global flag it finds every word character in the input, making it useful for tokenizing text, counting alphanumeric characters, or validating identifiers. The multiline flag has no effect here since the pattern contains no anchors like ^ or $.