def checkLetter(kataPertama:str, kataKedua:str)-> bool:
	kataPertamaLower = kataPertama.lower()
	kataKeduaLower = kataKedua.lower()
	for i in kataPertamaLower:
		if i not in kataKeduaLower:
			return False
	return True

print(checkLetter('cat','antarctica'))
print(checkLetter('cat','australia'))
print(checkLetter('cat','ANTARCTICA'))