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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 rslv(self, interface: str, name: str=None) -> Tuple[str, int, Optional[str]]: 		"""Return the IP address, port and optionally host IP for one of this Nodes interfaces."""

		if name is None:
			name = self.name
		key = '{}-{}'.format(name, interface)
		host = None
		if 'host' in self.interfaces[key]:
			host = self.interfaces[key]['host']
		return self.interfaces[key]['ip'], self.interfaces[key]['port'], host