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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 is_reachable(self):
 """Return if host is reachable."""

        if self.verify_reachability and \
                hasattr(self.verify_reachability, '__call__'):
            return self.verify_reachability(host=self.hostname, port=self.port)
        # assume is reachable if can't verify
        return True