online tool to describe regex code example

Example 1: python regex tester

Find below are online regex tester

https://regex101.com/
https://pythex.org/
http://www.pyregex.com/
https://www.debuggex.com/
  
Here you insert your regular expression and get the test result.
Thank you !!!

Example 2: regex /

// replaces all / in a String with _
str = str.replace(/\//g,'_');