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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 minutes_played(self):
 """ Returns a ``float`` of the number of game minutes the player was on the court for. """

        if self._minutes_played[self._index]:
            minutes, seconds = self._minutes_played[self._index].split(':')
            minutes = float(minutes) + float(seconds) / 60
            return float(minutes)
        return None