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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 _interface_exists(self, interface):
 """Check whether interface exists."""

        ios_cfg = self._get_running_config()
        parse = HTParser(ios_cfg)
        itfcs_raw = parse.find_lines("^interface " + interface)
        return len(itfcs_raw) > 0