在Python中，如何让用户修改类中字典的值？

Question

我之前有个类似的问题，在另一个讨论串里得到了答案。

简单来说，我想通过用户输入来修改一个嵌套字典的值。我用那个解决方案试了一下，效果很好，但我想用类来写这个程序。所以我创建了一个类，里面有一个方法来编辑字典，基本上用的是相同的代码，但当我在类的方法中运行时，却出现了“键错误”。

在主函数中，上面链接的问题的解决方案运行得很好。但是在类的方法中：

class team: # create a class where each team will be an instance
  def __init__(self, name):
    self.name = name #name of team will be passed from main
    self.list_of_players = [] # create a list of the players
    self.position1 = {} # create a dictionary for each of the positions on that team
    self.position2 = {}
    self.roster = [self.position1, self.position2]

  def addplayer(self, player_name): # the name of the player is passed to this method from main
    print 'add stats' # fill out the appropriate stats through raw_input 
    stat1 = raw_input('stat1: ')
    stat2 = raw_input('stat2: ')
    pos = raw_input('POS: ')
    vars()[player_name] = {'stat1' : stat1, 'stat2' : stat2, 'POS' : pos} #create a dictionary 
    # for the player where all his stats are kept
    player = {player_name : vars()[player_name]} # create a dictionary that will show the 
    # player's name as a string and his stats which are held in the dictionary named after him
    self.list_of_players.append(player) # append the new player to the list of players
    if pos == 'p1': # add the player and his stats to the appropriate position on the team
      self.position1[player_name] = player
    elif pos == 'p2':
      self.position2[player_name] = player
    else:
      pass

  def editplayer(self, player_name): # player's name is passed to the edit function from main
    print self.list_of_players # player's name shows up in the list of players for the team
    edit_stat = raw_input('which stat? ') # choose which stat(key) to edit via raw input
    new_value = raw_input('new value: ') # choose the new value to apply to the chosen key
    vars()[player_name][edit_stat] = new_value # here is where it gives a key error! this worked 
 #in fact even trying to call and print the players name gives the key error. 
    #player = vars()[player_name]
    #print player

def main(): # the main function
  loop1 = 0 # creating a loop so one can come back and edit the teams after creating them
  list_of_teams = [] # initializing list of teams
  while loop1 < 1:
    print list_of_teams # show the user what teams are available to choose from
    team_option = raw_input('new team or old: ') # create a new team or work with an old one
    if team_option == 'new':
      team_name = raw_input('team name? ') # get the team name from raw_input
      vars()[team_name] = team(team_name) #create an instance of this team name
      list_of_teams.append(team_name) # add the team to the list
    else:
      team_name = raw_input('which team? ') # choose which existing team to work with
      player_choice = raw_input('new player or old? ') # choose to create or edit existing player
      player_name = raw_input('player_name? ') # choose which player from raw_input
      if player_choice == 'new':
        vars()[team_name].addplayer(player_name) # give player_name to addplayer method 
        print vars()[team_name].list_of_players # shows the new player in the appropriate
        # instance's roster. This method seems to be working fine
      else:
        vars()[team_name].editplayer(player_name) # gives the player's name to the editplayer
        # method for the appropriate instance.  But the player name just raises a key error in
        # edit player method.  I am baffled.
        print vars()[team_name].list_of_players
if __name__ == '__main__':
  main()

当所有代码都放在一个长函数里时，这个方法是有效的，但看起来很糟糕。我在努力学习更好的面向对象编程（OOP）实践，但我搞不清楚如何通过玩家的名字来调用那个字典以改变它的值。我花了几天时间在复习关于类和字典的教程和问题，但显然我对变量是如何从函数传递到方法中有些误解。

我觉得它甚至无法将字典 vars()[player_name] 赋值给一个变量以便打印出来，这意味着它没有识别出这是在 addplayer 方法中创建的字典。但它仍然在玩家列表中列出那个字典，说明它在那个实例中是存在的。那么为什么在我尝试在 editplayer 方法中访问它时，它却不识别呢？我该如何调用在一个方法中创建的嵌套字典，以便在第二个方法中改变那个字典里的值呢？

Karl 提出了需要澄清的好点子：这是我想要的属性。

self.name - 我想为每个创建的队伍实例化一个名字

self.list of players - 每个队伍应该有自己的球员列表，这些列表是字典，记录着每个球员的统计数据。所以 team1 应该有自己的列表，team2 则有不同的列表等等。

self.position1/2 - 每个队伍的球员会被分类到他们各自的位置字典中。所以像乔·蒙塔纳这样的球员的统计数据字典会在那个队伍的四分卫字典中找到。

self.roster - 应该是按位置分组的队伍名单。所以调用 print team1.roster 应该会打印出按位置分组的球员。

面向对象编程数据结构字典操作方法调用实例化嵌套字典键错误玩家统计

在Python中，如何让用户修改类中字典的值？

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