C[C@H]1CC[C@H]2C(=O)N3[C@@H](CC[C@H](C)[C@H]3c3ccc(Br)cc3)C(=O)N2[C@@H]1c1ccc(Br)cc1
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?