Arduino: 1.8.5 (Windows 10), Board: "Arduino/Genuino Uno"

C:\Users\Walfa\Documents\Arduino\sketch_oct19b\sketch_oct19b.ino:34:24: fatal error: MySensor.h: No such file or directory

 #include <MySensor.h>

                        ^

compilation terminated.

exit status 1
Error compiling for board Arduino/Genuino Uno.

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