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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def regex_replace(arg, pattern, replacement):
 """ Replaces match found by regex with replacement string. Replacement string can also be a regex Parameters pattern : string (regular expression string) replacement : string (can be regular expression string) Examples -------- Returns ------- modified : string """

    return ops.RegexReplace(arg, pattern, replacement).to_expr()