iter.py

class Lineup:

    def __init__(self, players):
        self.players = players

    def __iter__(self):
        self.n = 0
        return self

    def __next__(self):
        if self.n < (len(self.players) - 1):
            player = self.players[self.n]
            self.n += 1
            return player
        elif self.n == (len(self.players) - 1):
            player = self.players[self.n]
            self.n = 0
            return player


astros = [
  'Springer',
  'Bregman',
  'Altuve',
  'Correa',
  'Reddick',
  'Gonzalez',
  'McCann',
  'Davis',
  'Tucker'
]

astros_lineup = Lineup(astros)
process = iter(astros_lineup)

print(next(process))
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