Question: so this piece of code is meant to take a line from a file and replace the certain line from the string with a new word/number, but it doesn't seem to work :(

```
else:
    with open('newfile', 'r+')as myfile:
           x=input("what would you like to change: \nname \ncolour \nnumber \nenter   option:")
           if x == "name":
               print("your current name is:")
               test_lines = myfile.readlines()
               print(test_lines[0])
               y=input("change name to:")
               content = (y)
               myfile.write(str.replace((test_lines[0]), str(content)))

```

I get the error message TypeError: replace() takes at least 2 arguments (1 given), i don't know why (content) is not accepted as an argument. This also happens for the code below

```
if x == "number":
          print ("your current fav. number is:")
          test_lines = myfile.readlines()
          print(test_lines[2])
          number=(int(input("times fav number by a number to get your new number \ne.g 5*2 = 10 \nnew number:")))
          result = (int(test_lines[2])*(number)) 
          print (result)
          myfile.write(str.replace((test_lines[2]), str(result)))

f=open('newfile', 'r')
print("now we will print the file:")
for line in f:
    print (line)
f.close

```

Answer: 
.05 seconds is too short an interval to do any meaningful animation. Think in terms of .1 seconds or so at a minimum.

If you can't get animations to work, post your code. Also tell us if you are using Storyboards (the default) or XIB files.
You really need to have a look at :

1. <http://tech.pro/tutorial/968/iphone-tutorial-reading-the-accelerometer>
2. **[iTuneU - Standford - Developing iOS 7 Apps for iPhone and iPad](https://itunes.apple.com/us/course/developing-ios-7-apps-for/id733644550) - video 17. Camera, Core Motion, Application Lifecycle**

If you have time, Standford course on iPhone/iPad Dev are TOP !