def WritePushPop(self, commandType, segment, index):

    	if commandType == C_PUSH:

    		if segment == 'static':
    			self._StaticLabel += '@' + str(index), 'D=M'

    		elif segment == 'constant':
    			self._WriteCode += '@' + str(index), 'D=A'

    		elif segment == 'pointer':
    			self._WriteCode += '@' + str(3 + index), 'D=M' #holds the addresses for this and that segments

    		elif segment == 'temp':
    			self._WriteCode += '@' + str(5 + index), 'D=M' #temp location starts at 5, Stack pointer at 0, local at 1 and argument at 2, pointer at  3 & 4

    		elif segment == 'this':
    			self._WriteCode += '@THIS, A=M, D=M'

    		elif segment == 'that':
    			self._WriteCode += '@THAT, A=M, D=M'

    		elif segment == 'local':
    			self._WriteCode += '@LCL, A=M, D=M'

    		elif segment == 'argument':
    			self._WriteCode += '@ARG, A=M, D=M'

    		self._WriteCode += ',@SP, AM=M+1, A=A-1, M=D'


		else: #else pop
			self._WriteCode += '@SP, AM=M-1, D=M,'
			if segment == 'static':
				self._WriteCode += '@' + str(5 + index) + ',M=D'

			elif segment == 'pointer':
				self._WriteCode += '@' + str(3 + index), 'M=D'

			elif segmnet == 'temp':
				self._WriteCode += '@' + str(5 + index), 'M=D'

			elif segment == 'this':
    			self._WriteCode += '@THIS, A=M, M=D'

    		elif segment == 'that':
    			self._WriteCode += '@THAT, A=M, M=D'

    		elif segment == 'local':
    			self._WriteCode += '@LCL, A=M, M=D'

    		elif segment == 'argument':
    			self._WriteCode += '@ARG, A=M, M=D'