如何从字典中调用函数

Question

我正在尝试从字典中调用函数，但不断收到一条错误消息，指出name: one_1_1 is not defined on line 11。

我不确定如何解决这个问题，我已经浏览了这个网站，并且认为我已经正确地完成了所有事情，但是当我尝试运行我的程序时，该错误一直在发布。 请帮忙。

def choice():
    choice = raw_input(prompt)
    choice.lower()

def wall():
    print "You ran into a wall."
    print "Try again... "

def really():
    print "Don't you know how to give directions?"
    print "Try again..."

prompt = "> "
n = "north"
s = "south"
e = "east"
w = "west"
loop = True

i = {
    #first number represents the row 
    #second number represents the column
    11: one_1_1, 
    12: one_1_2,
    21: one_2_1
}


def one_1_1():
    "You are in a dark room"
    "Which way do you go?"
    left_corner(11)

def one_2_1():
    print "I am what you get when"
    print "you go south"

def one_1_2():
    print "This is what you get when"
    print "You go east"

def left_corner(position):
    choice()
    while loop == True:

        if choice == n:
            wall()
            i[position]()

        elif choice == s:
            i[position + 10]()

        elif choice == e:
            i[position + 1]()

        elif choice == w:
            wall()
            i[position]()
        else: 
            really()

one_1_1()