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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 _redirect_output(self, value, filename=None, append=None, printfun=None):
 """Outputs the specified value to the console or a file depending on the redirect behavior specified. :arg value: the string text to print or save. :arg filename: the name of the file to save the text to. :arg append: when true, the text is appended to the file if it exists. """

        if filename is None:
            if printfun is None:
                print(value)
            else:
                printfun(value)
        else:
            if append:
                mode = 'a'
            else:
                mode = 'w'

            from os import path
            fullpath = path.abspath(filename)
            with open(filename, mode) as f:
                f.write(value + '\n')