O=C1OC(OC/C(Br)=C(\Br)COC2OC(=O)C(Cl)=C2Cl)C(Cl)=C1Cl
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?