I am still a beginner please help.Python programmers : I am still at the learning process of python,so I am a beginner obviously.I have got a question.That is a code that is written in python that should encrypt the word or sentence the user inputs.It should change every letter or number to the next one.but it doesn't work.like if I throw:**abcdefghijklmnopqrstuvwxyz1234567890**, it returns:**cceeggiikkmmooqqssuuwwyyaa2355679902**.How can I solve this and why doesn't it work?Please help ASAP
Here is the code:

 

       joka = raw_input("PLease enter a word:" )
    
    
    def replace_all(text, dic):
        for i, j in dic.iteritems():
            text = text.replace(i, j)
        return text
    
    reps = {'a':'b', 'b':'c', 'c':'d', 'd':'e', 'e':'f', 'f':'g', 'g':'h', 'h':'i', 'i':'j', 'j':'k', 'k':'l', 'l':'m', 'm':'n', 'n':'o', 'o':'p', 'p':'q', 'q':'r', 'r':'s', 's':'t', 't':'u', 'u':'v', 'v':'w', 'w':'x', 'x':'y', 'y':'z', 'z':'a', '1':'2', '2':'3', '3':'4', '4':'5', '5':'6', '6':'7', '7':'8', '8':'9', '9':'0', '0':'1'}
    
    j0ka = replace_all(joka, reps)
    print j0ka