class Classroom:

    def __init__(self, subject, teacher, nstudents, nta = 0, maxstudents = 30):
    	self.subject = subject
    	self.teacher = teacher
    	self.students = nstudents
    	self.nta = nta
    	self.maxstudents = maxstudents

    def getsubject(self):
    	return self.subject

    def getteacher(self):
    	return self.teacher

    def getnstudents(self):
    	return self.students

    def getnta(self):
    	return self.nta

    def getmaxstudents(self):
    	return self.maxstudents

    def setmaxstudents(self, maxval):
    	self.maxstudnets = maxval

    def setta(self, ta):
    	self.nta = ta

    def addstudent(self, num):
        'increments the number of students in the class by num up to the max'
        self.students += 1

    def dropstudent(self, num):
        'decrements the number of students in the class by num down to 0'
        self.students -= 1