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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 register(self, command, description, function, params=[]):
 """ Registers a new command for a plugin. :param command: Name of the command :param description: Description of the command. Is used as help message on cli :param function: function reference, which gets invoked if command gets called. :param params: list of click options and arguments :return: command object """

        return self.app.commands.register(command, description, function, params, self.plugin)