title: IndexError:list index out of range. This is while encrypting
body: <p>I have been coding with Python for a few months, and I have already coded a successful cipher, but I am making a random cipher and it won't work. I have attached the code.</p>
  
  <pre><code>    txt=input("Input message.\n")
    numbers=[1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26]
    ra.shuffle(numbers)
    a1=numbers[1]
    b1=numbers[2]
    c1=numbers[3]
    d1=numbers[4]
    e1=numbers[5]
    f1=numbers[6]
    g1=numbers[7]
    h1=numbers[8]
    i1=numbers[9]
    j1=numbers[10]
    k1=numbers[11]
    l1=numbers[12]
    m1=numbers[13]
    n1=numbers[14]
    o1=numbers[15]
    p1=numbers[16]
    q1=numbers[17]
    r1=numbers[18]
    s1=numbers[19]
    t1=numbers[20]
    u1=numbers[21]
    v1=numbers[22]
    w1=numbers[23]
    x1=numbers[24]
    y1=numbers[25]
    z1=numbers[26]
    alphabet=['a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z']
    a=alphabet[a1]
    b=alphabet[b1]
    c=alphabet[c1]
    d=alphabet[d1]
    e=alphabet[e1]
    f=alphabet[f1]
    g=alphabet[g1]
    h=alphabet[h1]
    i=alphabet[i1]
    j=alphabet[j1]
    k=alphabet[k1]
    l=alphabet[l1]
    m=alphabet[m1]
    n=alphabet[n1]
    o=alphabet[o1]
    p=alphabet[p1]
    q=alphabet[q1]
    r=alphabet[r1]
    s=alphabet[s1]
    t=alphabet[t1]
    u=alphabet[u1]
    v=alphabet[v1]
    w=alphabet[w1]
    x=alphabet[x1]
    y=alphabet[y1]
    z=alphabet[z1]
    txta=txt.replace("a","á")
    txtb=txta.replace("b","+")
    txtc=txtb.replace("c","ç")
    txtd=txtc.replace("d","ð")
    txte=txtd.replace("e","é")
    txtf=txte.replace("f","đ")
    txtg=txtf.replace("g","ŋ")
    txth=txtg.replace("h","ħ")
    txti=txth.replace("i","í")
    txtj=txti.replace("j","j̉")
    txtk=txtj.replace("k","ĸ")
    txtl=txtk.replace("l","ł")
    txtm=txtl.replace("m","µ")
    txtn=txtm.replace("n","n̉")
    txto=txtn.replace("o","ó")
    txtp=txto.replace("p","þ") 
    txtq=txtp.replace("q","@")
    txtr=txtq.replace("r","¶")
    txts=txtr.replace("s","ß")
    txtt=txts.replace("t","ŧ")
    txtu=txtt.replace("u","ú")
    txtv=txtu.replace("v","̉")
    txtw=txtv.replace("w","ẃ")
    txtx=txtw.replace("x","»")
    txty=txtx.replace("y","ý")
    txtz=txty.replace("z","«")
    texta=txtz.replace("á",a)
    textb=texta.replace("+",b)
    textc=textb.replace("ç",c)
    textd=textc.replace("ð",d)
    texte=textd.replace("é",e)
    textf=texte.replace("đ",f)
    textg=textf.replace("ŋ",g)
    texth=textg.replace("ħ",h)
    texti=texth.replace("í",i)
    textj=texti.replace("j̉",j)
    textk=textj.replace("ĸ",k)
    textl=textk.replace("ł",l)
    textm=textl.replace("µ",m)
    textn=textm.replace("n̉",n)
    texto=textn.replace("ó",o)
    textp=texto.replace("þ",p)
    textq=textp.replace("@",q)
    textr=textq.replace("¶",r)
    texts=textr.replace("ß",s)
    textt=texts.replace("ŧ",t)
    textu=textt.replace("ú",u)
    textv=textu.replace("̉",v)
    textw=textv.replace("ẃ",w)
    textx=textw.replace("»",x)
    texty=textx.replace("ý",y)
    text=texty.replace("«",z)
    print(text)
  </code></pre>
  
  <p>It just comes up with IndexError: list index out of range. Anybody got any idea why? It affects the letter z, and when I remove it, it affects the letter j. And if you're wondering why there are special characters, it's so that if a goes to z and z goes to a then a will go to z which will then go back to a. I call it double substitution.</p>