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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 append_note(self, note, root, scale=0):
 """ Append a note to quality :param str note: note to append on quality :param str root: root note of chord :param int scale: key scale """

        root_val = note_to_val(root)
        note_val = note_to_val(note) - root_val + scale * 12
        if note_val not in self.components:
            self.components.append(note_val)
            self.components.sort()