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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 center(self, width, fillchar=None):
 """Return centered in a string of length width. Padding is done using the specified fill character or space. :param int width: Length of output string. :param str fillchar: Use this character instead of spaces. """

        if fillchar is not None:
            result = self.value_no_colors.center(width, fillchar)
        else:
            result = self.value_no_colors.center(width)
        return self.__class__(result.replace(self.value_no_colors, self.value_colors), keep_tags=True)