What is Regex?
A Regular Expression (Regex) is a sequence of characters that defines a search pattern. Usually such patterns are used by string-searching algorithms for “find” or “find and replace” operations, or for input validation. It is a technique developed in theoretical computer science and formal language theory.
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More About Regex
Matching a regular expression against a string can be done in a number of ways. A common method is to use the regex module in Python’s standard library, which provides a number of functions and methods for working with regular expressions.
Regular expressions can be used to perform a variety of tasks, such as validation, and search and replace. They’re also used for input validation, to make sure that only certain characters are allowed in a given string.
Regular expressions are a powerful tool, but they can be difficult to use. You can use a regular expression debugger, such as RegexBuddy, to help you create and test your regular expressions.