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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 completedefault(self, text, line, begidx, endidx):
 """Accessing the argcompleter if available."""

        if self.argparser_completer and any((line.startswith(x) for x in self.argparse_names())):
            self.argparser_completer.rl_complete(line, 0)
            return [x[begidx:] for x in self.argparser_completer._rl_matches]
        else:
            return []