CC1C(=O)CCC2[C@]1(C)CCC1[C@]3(C)CC[C@@]4(C)CCC(C)(C)CC4[C@]3(C)CC[C@]21C
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?