Add input command for unix
diff --git a/unix/mpconfigport.h b/unix/mpconfigport.h
index 41bc6a3..ca470d9 100644
--- a/unix/mpconfigport.h
+++ b/unix/mpconfigport.h
@@ -72,6 +72,8 @@
 typedef void *machine_ptr_t; // must be of pointer size
 typedef const void *machine_const_ptr_t; // must be of pointer size
 
+extern const struct _mp_obj_fun_native_t mp_builtin_input_obj;
 extern const struct _mp_obj_fun_native_t mp_builtin_open_obj;
 #define MICROPY_EXTRA_BUILTINS \
+    { MP_OBJ_NEW_QSTR(MP_QSTR_input), (mp_obj_t)&mp_builtin_input_obj }, \
     { MP_OBJ_NEW_QSTR(MP_QSTR_open), (mp_obj_t)&mp_builtin_open_obj },