python中从文件中读取数据

 # average5.py
 def main():
     fileName = input("What file are the numbers in?")
     infile = open(fileName, 'r')
     sum = 0
     count = 0
     for line in infile:
         sum = sum + eval(line)
         count = count + 1
     print("\nThe average of the numbers is ",sum/count)
 main()

 #================= RESTART: C:/Users/home/Desktop/average.py =================
 #What file are the numbers in?C:\Users\home\Desktop\python4\num.txt

 #The average of the numbers is  10.5

在运行代码时必须将文件的路径以及文件的名称，还有文件的后缀输入。