O=C(O)CSc1c2c(nc3cc(C(=O)Nc4ccc(F)c(Cl)c4)ccc13)CCCC2
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?