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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 _MapVowels(cls, string, also_p=False):
 """ Return a copy of ``string`` where characters that exist as keys in cls._VOWELS have been replaced with the corresponding value. If also_p is True, this function will also change capital P characters into a Hebrew character Qof. """

        return cls._PSUB_RE.sub(cls.Repl, string)