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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 onecmd(self, line):
 """Interpret the argument as though it had been typed in response to the prompt. Checks whether this line is typed at the normal prompt or in a breakpoint command list definition. """

        if not self.commands_defining:
            return cmd.Cmd.onecmd(self, line)
        else:
            return self.handle_command_def(line)