def setup(self, filename):
#read txt file
#construct attr
grammar_file = open(filename)
line_count = 0
for line in grammar_file:
line = line.strip('\n')
if (line_count == 0):
self.start = line.split(' ')[0]
self.nonterminal = set(line.split(' '))
elif (line_count == 1):
self.terminal = set(line.split(' '))
else:
rule = Rule()
rule.setRule(line.split(' '))
self.rule.append(rule)
line_count += 1
