Sleep 1 second after finish the work in each thread

wrapper.pyx

 from lwan_coro cimport scheduler_t, scheduler_init, scheduler_coro_add, scheduler_run, scheduler_destroy, coro_yield_value, coro_yield, coro_t
 from libc.stdio cimport printf
 
+cdef extern from "unistd.h" nogil:
+  unsigned int sleep(unsigned int seconds)
+
 cdef class SomeMemory nogil:
   cdef int a;
   cdef int b;
@@ -8,6 +11,7 @@ cdef class SomeMemory nogil:
     while self.a < 4:
       self.a += 1
       printf("%d\n", self.a)
+      sleep(1)
 
 def main():
   cdef: