def system_address
      ::Socket.ip_address_list.find { |address|
        address.ipv4? && !address.ipv4_loopback?
      }.ip_address rescue nil
    end
def system_address
      ::Socket.ip_address_list.find { |address|
        address.ipv4? && !address.ipv4_loopback?
      }.ip_address rescue nil
    end
Retrieve the system IP address. If a valid non-loopback
 IPv4 address cannot be found and an error is thrown,
 `nil` will be returned.

 @return [String] system ip address