O=C1C(c2ccccc2)=C(c2ccccc2)C(c2ccc(Cc3ccc(C4=C(c5ccccc5)C(=O)C(c5ccccc5)=C4c4ccccc4)cc3)cc2)=C1c1ccccc1
A rotatable bond is defined as any single non-ring bond, attached to a non-terminal, non-hydrogen atom. Amide C-N bonds are not counted because of their high barrier to rotation.  How many rotatable bonds does the molecule have?