Regular Expression Replace ChallengeIn this challenge you will use the file regex_replace_challenge_student. py to:Write a regular expression that will replace all occurrences of:regular-expressionregular:expres sion regular&expressionIn the string: This is a string to search for a regular expression like regular expression or regular-expression orregular:expression or regular&expressionAssign the regular expression to a variable named patternUsing the sub() method from the re package substitute all occurrences of the 'pattern' with 'substitution'Assign the outcome of the sub() method to a variable called replace_resultOutput to the console replace_resultsRegular Expression Replace ChallengeThe Python statement containing the string to search for the regular expression occurrence is below. search_string=’’’This is a string to search for a regular expression like regular expression or regular-expression or regular:expression or regular&expression’’’Write a regular expression that will find all occurrences of:a. regular expressionb. regular-expressionc. regular:expressiond. regular&expression in search_string