/in/foo.c:1:1: error: unknown type name 'def'
 def change_status(list_x, b):
 ^~~
/in/foo.c: In function 'change_status':
/in/foo.c:1:29: error: expected declaration specifiers before ':' token
 def change_status(list_x, b):
                             ^
/in/foo.c:1:5: warning: type of 'list_x' defaults to 'int' [-Wimplicit-int]
 def change_status(list_x, b):
     ^~~~~~~~~~~~~
/in/foo.c:1:5: warning: type of 'b' defaults to 'int' [-Wimplicit-int]
/in/foo.c:41:1: warning: control reaches end of non-void function [-Wreturn-type]
 print(str_output)
 ^~~~~