Remove shebang from all files except required
diff --git a/apply_license.sh b/apply_license.sh
index a7a1061..fee9890 100755
--- a/apply_license.sh
+++ b/apply_license.sh
@@ -3,8 +3,10 @@
     if ! grep -q Copyright $f; then
         cat COPYRIGHT.txt $f > $f.license.py
         mv $f.license.py $f
-        #prepend shebang for python
-        sed -i -e '/^\#\!\/usr\/bin/d' -e '1i\#\!/usr/bin/env python' $f
-        chmod +x $f
+        if grep -q "^\#\!/usr/bin" $f; then
+          #prepend shebang for python
+          sed -i -e '/^\#\!\/usr\/bin/d' -e '1i\#\!/usr/bin/env python' $f
+          chmod +x $f
+        fi
     fi
 done