code: def unassign_floating_ip(self, ip_addr):
          
          if self.api_version == 2:
              params = {'type': 'unassign'}
  
              json = self.request('/floating_ips/' + ip_addr + '/actions', params=params, method='POST')
              return json['action']
          else:
              raise DoError(v2_api_required_str)
docs: Unassign a Floating IP from a Droplet.
          The Floating IP will be reserved in the region but not assigned to a Droplet.