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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 _get_binding_keys(self, port, host):
 """Get binding keys from the port binding"""

        binding_keys = list()
        switch_binding = port[portbindings.PROFILE].get(
            'local_link_information', None)
        if switch_binding:
            for binding in switch_binding:
                switch_id = binding.get('switch_id')
                port_id = binding.get('port_id')
                binding_keys.append((port['id'], (switch_id, port_id)))
        else:
            binding_keys.append((port['id'], host))
        return binding_keys