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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_input_buffer(self, text):

 """Set input buffer"""

        if self.current_prompt_pos is not None:
            self.replace_text(self.current_prompt_pos, 'eol', text)
        else:
            self.insert(text)
        self.set_cursor_position('eof')