'Parses a tuplet ratio.
Represented in MusicXML by the <time-modification> element.
Args:
xml_time_modification: An xml time-modification element.'

def _parse_tuplet(self, xml_time_modification):

    numerator = int(xml_time_modification.find('actual-notes').text)
    denominator = int(xml_time_modification.find('normal-notes').text)
    self.note_duration.tuplet_ratio = Fraction(numerator, denominator)
