sentence = "I practice : 3 hours in day"
def calculatHours(sentence,numberofDays):

    numberofDays=n - (n/4)
    return numberofDays*3

    result = calculatHours(sentence,numberofDays)
    print result
print calculatHours(sentence,3)
print calculatHours(sentence,4)
print calculatHours(sentence,5)
print calculatHours(sentence,6)
print calculatHours(sentence,10)
