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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 cmd_rally_alt(self, args):
        '''handle rally alt change'''
        if (len(args) < 2):
            print("Usage: rally alt RALLYNUM newAlt <newBreakAlt>")
            return
        if not self.have_list:
            print("Please list rally points first")
            return

        idx = int(args[0])
        if idx <= 0 or idx > self.rallyloader.rally_count():
            print("Invalid rally point number %u" % idx)
            return

        new_alt = int(args[1])
        new_break_alt = None
        if (len(args) > 2):
            new_break_alt = int(args[2])

        self.rallyloader.set_alt(idx, new_alt, new_break_alt)
        self.send_rally_point(idx-1)
        self.fetch_rally_point(idx-1)
        self.rallyloader.reindex()