Print.h cannot be included

■ Corresponding version  
v.2.0.0 and v.2.1.0

■ Contents and Occurrence conditions  
Including Print.h causes an error.

■ Workaround  
When including Print.h, write as follows.  
`#include "api/Print.h"` 

■ Permanent measures  
Scheduled to be fixed in V2.2.0.