全局變量1
全局變量2
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def 函數1():
  pass
def 函數2():
  pass
def 函數3():
  pass
def 函數4():
  pass
def 函數5():
  pass

class 類(object):
  屬性1
  屬性2
  def 方法1(self):
    pass
  def 方法2(self):
    pass
class 類2(object):
  屬性3
  def 方法3(self):
    pass
  def 方法4(self):
    pass
  def 方法5(self):
    pass

class MiniOS(object):
  """MiniOS 操作系統類 """
  def __init__(self, name):
    self.name = name
    self.apps = [] # 安裝的應用程序名稱列表
  def __str__(self):
    return "%s 安裝的軟件列表為 %s" % (self.name, str(self.apps))
  def install_app(self, app):
    # 判斷是否已經安裝了軟件
    if app.name in self.apps:
      print("已經安裝了 %s，無需再次安裝" % app.name)
    else:
      app.install()
      self.apps.append(app.name)
class App(object):
  def __init__(self, name, version, desc):
    self.name = name
    self.version = version
    self.desc = desc
  def __str__(self):
    return "%s 的當前版本是 %s - %s" % (self.name, self.version, self.desc)
  def install(self):
    print("將 %s [%s] 的執(zhí)行程序復制到程序目錄..." % (self.name, self.version))
class PyCharm(App):
  pass
class Chrome(App):
  def install(self):
    print("正在解壓縮安裝程序...")
    super().install()
linux = MiniOS("Linux")
print(linux)
pycharm = PyCharm("PyCharm", "1.0", "python 開發(fā)的 IDE 環(huán)境")
chrome = Chrome("Chrome", "2.0", "谷歌瀏覽器")
linux.install_app(pycharm)
linux.install_app(chrome)
linux.install_app(chrome)
print(linux)