ex48.main.py

class lexicon(object):

	direction	=	['north', 'south'	, 'east'	, 'west', 'down', 'up', 'left', 'right', 'back'] 
	verb 		=	['go'	, 'stop'	, 'kill'	, 'eat']
	stop		=	['the'	, 'in'		, 'of'		, 'from', 'at'	, 'it'] 
	noun 		=	['door'	, 'bear'	, 'princess', 'cabinet']	
	finalList	=	[]
	
	

	@staticmethod
	def isnum(s):
		try:
			return int(s)
		except ValueError:
			return None
	@staticmethod
	def scan(sentence):
		
		
		
		lexicon.finalList = []  
		words = sentence.split(" ") 
		for i in words:
			if lexicon.isnum(i):
				newGroup = ('number' , int(i))
				lexicon.finalList.append(newGroup)
			else:
				flag = 0

				for ii in lexicon.direction:
					if ii == i:
						newGroup = ('direction', ii)
						lexicon.finalList.append(newGroup)
						flag = 1

				for ii in lexicon.verb:
					if ii == i and flag != 1:
						newGroup = ('verb', ii)
						lexicon.finalList.append(newGroup)
						flag = 1

				for ii in lexicon.stop:
					if ii == i and flag != 1:
						newGroup = ('stop', ii)
						lexicon.finalList.append(newGroup)
						flag = 1

				for ii in lexicon.noun:
					if ii == i and flag != 1:
						newGroup = ('noun', ii)
						lexicon.finalList.append(newGroup)
						flag = 1

				
				
				
				if flag != 1: 
					newGroup = ('error', i)
					lexicon.finalList.append(newGroup)

		return lexicon.finalList