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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 is_valid_hendecasyllables(self, scanned_line: str) -> bool: """Determine if a scansion pattern is one of the valid Hendecasyllables metrical patterns :param scanned_line: a line containing a sequence of stressed and unstressed syllables :return bool True """

        line = scanned_line.replace(self.constants.FOOT_SEPARATOR, "")
        line = line.replace(" ", "")
        if len(line) < 11:
            return False
        line = line[:-1] + self.constants.OPTIONAL_ENDING
        return self.VALID_HENDECASYLLABLES.__contains__(line)