Python中eval表达式判断是否合法问题

我是用的tkinter的从Text获取输入，然后用eval（）求值，当输入的表达式错误的时候，会有unexpected EOF while parsing，如何判断这种情况然后提示表达式错误？
self.result=tkinter.Toplevel(self.main)
self.result.title('')
self.result.geometry('160x80+100+120')
if(eval(exp.get('1.0','1.end'))==24):
Label(self.result,text='恭喜，回答正确！',font=('微软雅黑',10)).place(relx = 0.5,rely = 0.3,anchor = CENTER)
bt_1=Button(self.result,text='下一题',width=5,height=1,command = lambda:self.next_question(exp)).place(relx = 0.5,rely = 0.8,anchor = CENTER)
elif(eval(exp.get('1.0','1.end'))==EOF):
Label(self.result,text='请输入正确的表达式！',font=('微软雅黑',10)).place(relx = 0.5,rely = 0.3,anchor = CENTER)
bt_1=Button(self.result,text='确定',width=5,height=1,command = lambda:self.result.destroy()).place(relx = 0.5,rely = 0.8,anchor = CENTER)
else:
Label(self.result,text='很遗憾，回答错误',font=('微软雅黑',10)).place(relx = 0.5,rely = 0.3,anchor = CENTER)
bt_1=Button(self.result,text='查看答案',width=6,height=1,command = lambda:slef.Get_Answer()).place(relx = 0.3,rely = 0.8,anchor = CENTER)
bt_2=Button(self.result,text='下一题',width=5,height=1,command = lambda:self.next_question(exp)).place(relx = 0.7,rely = 0.8,anchor = CENTER)

总感觉你和我做的是同一个作业………………
该不会是24点吧!!!!