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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 execute(self):
 """Execute Slackware command """

        if self.choice in self.commands.keys():
            if self.choice == "i":
                PackageManager(self.packages).install("")
            elif self.choice in ["u", "r"]:
                PackageManager(self.packages).upgrade(
                    self.commands[self.choice][11:])