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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 assert_free(self, host, port=None):
 		""" 		Assert that the given addr is free 		in that all attempts to connect fail within the timeout 		or raise a PortNotFree exception. 		Also accepts an addr tuple 		Host might refer to a server bind address like '::', which 		should use localhost to perform the check. 		"""

		if port is None and isinstance(host, abc.Sequence):
			host, port = host[:2]
		if platform.system() == 'Windows':
			host = client_host(host)
		info = socket.getaddrinfo(
			host, port, socket.AF_UNSPEC, socket.SOCK_STREAM,
		)
		list(itertools.starmap(self._connect, info))