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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 set_prompt(self):
 """The prompt is important because we detect the readyness of a process by waiting for its prompt."""

        # No right prompt
        command_line = b'PS2=;RPS1=;RPROMPT=;'
        command_line += b'PROMPT_COMMAND=;'
        command_line += b'TERM=ansi;'
        command_line += b'unset HISTFILE;'
        prompt1, prompt2 = callbacks.add(b'prompt', self.seen_prompt_cb, True)
        command_line += b'PS1="' + prompt1 + b'""' + prompt2 + b'\n"\n'
        return command_line