Pattern Matcher with Dictionary Substitution

Question Given a string str and a dictionary dict, where the string contains patterns enclosed within %. Replace each pattern with the value in the dictionary. If a value cannot be found, return error. Input A string str with patterns in the format %pattern%. A dictionary dict with patterns as keys and replacement strings as values. Output The modified string after replacement. If substitution fails, return error. Example Input: str = "a%sd%fasd%dog%sdfisan", dict = {"sd": "START", "dog": "DOG"} Output: "aSTARTfasdDOGsdfisan" Input: str = "%rat% in the %hat%", dict = {"cat": "CAT"} Output: "error" Example Input "a%sd%fasd%dog%sdfisan" {"sd": "START", "dog": "DOG"}